forked from lijiext/lammps
691 lines
27 KiB
C
691 lines
27 KiB
C
/// **************************************************************************
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// tersoff_zbl_extra.h
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// -------------------
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// Trung Dac Nguyen
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//
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// Device code for Tersoff math routines
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//
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// __________________________________________________________________________
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// This file is part of the LAMMPS Accelerator Library (LAMMPS_AL)
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// __________________________________________________________________________
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//
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// begin :
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// email : ndactrung@gmail.com
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// ***************************************************************************/*
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#ifndef LAL_TERSOFF_ZBL_EXTRA_H
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#define LAL_TERSOFF_ZBL_EXTRA_H
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#ifdef NV_KERNEL
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#include "lal_aux_fun1.h"
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#else
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#endif
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#define MY_PI (numtyp)3.14159265358979323846
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#define MY_PI2 (numtyp)1.57079632679489661923
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#define MY_PI4 (numtyp)0.78539816339744830962
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp vec3_dot(const numtyp x[3], const numtyp y[3])
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{
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return (x[0]*y[0] + x[1]*y[1] + x[2]*y[2]);
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}
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ucl_inline void vec3_add(const numtyp x[3], const numtyp y[3], numtyp z[3])
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{
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z[0] = x[0]+y[0]; z[1] = x[1]+y[1]; z[2] = x[2]+y[2];
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}
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ucl_inline void vec3_scale(const numtyp k, const numtyp x[3], numtyp y[3])
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{
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y[0] = k*x[0]; y[1] = k*x[1]; y[2] = k*x[2];
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}
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ucl_inline void vec3_scaleadd(const numtyp k, const numtyp x[3],
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const numtyp y[3], numtyp z[3])
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{
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z[0] = k*x[0]+y[0]; z[1] = k*x[1]+y[1]; z[2] = k*x[2]+y[2];
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp ters_gijk(const numtyp costheta,
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const numtyp param_c,
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const numtyp param_d,
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const numtyp param_h,
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const numtyp param_gamma)
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{
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const numtyp ters_c = param_c * param_c;
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const numtyp ters_d = param_d * param_d;
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const numtyp hcth = param_h - costheta;
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return param_gamma*((numtyp)1.0 + ters_c*ucl_recip(ters_d) -
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ters_c *ucl_recip(ters_d + hcth*hcth));
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp ters_gijk_d(const numtyp costheta,
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const numtyp param_c,
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const numtyp param_d,
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const numtyp param_h,
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const numtyp param_gamma)
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{
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const numtyp ters_c = param_c * param_c;
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const numtyp ters_d = param_d * param_d;
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const numtyp hcth = param_h - costheta;
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const numtyp numerator = (numtyp)-2.0 * ters_c * hcth;
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const numtyp denominator = ucl_recip(ters_d + hcth*hcth);
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return param_gamma*numerator*denominator*denominator;
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline void costheta_d(const numtyp rij_hat[3],
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const numtyp rij,
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const numtyp rik_hat[3],
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const numtyp rik,
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numtyp *dri,
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numtyp *drj,
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numtyp *drk)
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{
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// first element is derivative wrt Ri, second wrt Rj, third wrt Rk
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numtyp cos_theta = vec3_dot(rij_hat,rik_hat);
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vec3_scaleadd(-cos_theta,rij_hat,rik_hat,drj);
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vec3_scale(ucl_recip(rij),drj,drj);
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vec3_scaleadd(-cos_theta,rik_hat,rij_hat,drk);
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vec3_scale(ucl_recip(rik),drk,drk);
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vec3_add(drj,drk,dri);
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vec3_scale((numtyp)-1.0,dri,dri);
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp ters_fc(const numtyp r,
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const numtyp param_bigr,
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const numtyp param_bigd)
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{
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if (r < param_bigr-param_bigd) return (numtyp)1.0;
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if (r > param_bigr+param_bigd) return (numtyp)0.0;
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return (numtyp)0.5*((numtyp)1.0 - sin(MY_PI2*(r - param_bigr)/param_bigd));
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp ters_fc_d(const numtyp r,
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const numtyp param_bigr,
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const numtyp param_bigd)
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{
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if (r < param_bigr-param_bigd) return (numtyp)0.0;
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if (r > param_bigr+param_bigd) return (numtyp)0.0;
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return -(MY_PI4/param_bigd) * cos(MY_PI2*(r - param_bigr)/param_bigd);
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp F_fermi(const numtyp r, const numtyp param_ZBLcut,
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const numtyp param_ZBLexpscale)
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{
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return ucl_recip((numtyp)1.0+ucl_exp(-param_ZBLexpscale*(r-param_ZBLcut)));
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp F_fermi_d(const numtyp r, const numtyp param_ZBLcut,
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const numtyp param_ZBLexpscale)
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{
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numtyp a = ucl_exp(-param_ZBLexpscale*(r-param_ZBLcut));
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numtyp b = (numtyp)1.0 + a;
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return param_ZBLexpscale*a*ucl_recip(b*b);
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp ters_fa(const numtyp r,
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const numtyp param_bigb,
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const numtyp param_bigr,
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const numtyp param_bigd,
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const numtyp param_lam2,
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const numtyp param_ZBLcut,
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const numtyp param_ZBLexpscale)
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{
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if (r > param_bigr + param_bigd) return (numtyp)0.0;
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return -param_bigb * ucl_exp(-param_lam2 * r) *
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ters_fc(r,param_bigr,param_bigd)*F_fermi(r,param_ZBLcut,param_ZBLexpscale);
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp ters_fa_d(const numtyp r,
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const numtyp param_bigb,
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const numtyp param_bigr,
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const numtyp param_bigd,
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const numtyp param_lam2,
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const numtyp param_ZBLcut,
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const numtyp param_ZBLexpscale)
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{
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if (r > param_bigr + param_bigd) return (numtyp)0.0;
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numtyp f = F_fermi(r,param_ZBLcut,param_ZBLexpscale);
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return param_bigb * ucl_exp(-param_lam2 * r) *
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(param_lam2 * ters_fc(r,param_bigr,param_bigd) * f -
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ters_fc_d(r,param_bigr,param_bigd) * f -
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ters_fc(r,param_bigr,param_bigd) * F_fermi_d(r,param_ZBLcut,param_ZBLexpscale));
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp ters_bij(const numtyp zeta,
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const numtyp param_beta,
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const numtyp param_powern,
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const numtyp param_c1,
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const numtyp param_c2,
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const numtyp param_c3,
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const numtyp param_c4)
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{
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numtyp tmp = param_beta * zeta;
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if (tmp > param_c1) return ucl_rsqrt(tmp);
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if (tmp > param_c2)
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return ((numtyp)1.0 - ucl_powr(tmp,-param_powern) /
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((numtyp)2.0*param_powern))*ucl_rsqrt(tmp);
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if (tmp < param_c4) return (numtyp)1.0;
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if (tmp < param_c3)
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return (numtyp)1.0 - ucl_powr(tmp,param_powern)/((numtyp)2.0*param_powern);
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return ucl_powr((numtyp)1.0 + ucl_powr(tmp,param_powern),
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(numtyp)-1.0/((numtyp)2.0*param_powern));
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline numtyp ters_bij_d(const numtyp zeta,
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const numtyp param_beta,
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const numtyp param_powern,
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const numtyp param_c1,
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const numtyp param_c2,
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const numtyp param_c3,
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const numtyp param_c4)
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{
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numtyp tmp = param_beta * zeta;
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if (tmp > param_c1)
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return param_beta * (numtyp)-0.5*ucl_powr(tmp,(numtyp)-1.5);
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if (tmp > param_c2)
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return param_beta * ((numtyp)-0.5*ucl_powr(tmp,(numtyp)-1.5) *
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// error in negligible 2nd term fixed 9/30/2015
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// (1.0 - 0.5*(1.0 + 1.0/(2.0*param->powern)) *
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((numtyp)1.0 - ((numtyp)1.0 + (numtyp)1.0 /((numtyp)2.0 * param_powern)) *
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ucl_powr(tmp,-param_powern)));
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if (tmp < param_c4) return (numtyp)0.0;
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if (tmp < param_c3)
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return (numtyp)-0.5*param_beta * ucl_powr(tmp,param_powern-(numtyp)1.0);
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numtyp tmp_n = ucl_powr(tmp,param_powern);
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return (numtyp)-0.5 * ucl_powr((numtyp)1.0+tmp_n, (numtyp) -
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(numtyp)1.0-((numtyp)1.0 / ((numtyp)2.0 * param_powern)))*tmp_n / zeta;
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}
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/* ---------------------------------------------------------------------- */
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ucl_inline void ters_zetaterm_d(const numtyp prefactor,
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const numtyp rij_hat[3],
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const numtyp rij,
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const numtyp rik_hat[3],
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const numtyp rik,
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const numtyp param_bigr,
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const numtyp param_bigd,
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const numtyp param_powermint,
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const numtyp param_lam3,
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const numtyp param_c,
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const numtyp param_d,
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const numtyp param_h,
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const numtyp param_gamma,
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numtyp dri[3],
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numtyp drj[3],
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numtyp drk[3])
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{
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numtyp gijk,gijk_d,ex_delr,ex_delr_d,fc,dfc,cos_theta,tmp;
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numtyp dcosdri[3],dcosdrj[3],dcosdrk[3];
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fc = ters_fc(rik,param_bigr,param_bigd);
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dfc = ters_fc_d(rik,param_bigr,param_bigd);
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numtyp t = param_lam3*(rij-rik);
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if ((int)param_powermint == 3) tmp = t*t*t;
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else tmp = t;
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if (tmp > (numtyp)69.0776) ex_delr = (numtyp)1.e30;
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else if (tmp < (numtyp)-69.0776) ex_delr = (numtyp)0.0;
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else ex_delr = ucl_exp(tmp);
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if ((int)param_powermint == 3)
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ex_delr_d = (numtyp)3.0*param_lam3*t*t*ex_delr;
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else ex_delr_d = param_lam3 * ex_delr;
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cos_theta = vec3_dot(rij_hat,rik_hat);
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gijk = ters_gijk(cos_theta,param_c,param_d,param_h,param_gamma);
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gijk_d = ters_gijk_d(cos_theta,param_c,param_d,param_h,param_gamma);
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costheta_d(rij_hat,rij,rik_hat,rik,dcosdri,dcosdrj,dcosdrk);
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// compute the derivative wrt Ri
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// dri = -dfc*gijk*ex_delr*rik_hat;
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// dri += fc*gijk_d*ex_delr*dcosdri;
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// dri += fc*gijk*ex_delr_d*(rik_hat - rij_hat);
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vec3_scale(-dfc*gijk*ex_delr,rik_hat,dri);
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vec3_scaleadd(fc*gijk_d*ex_delr,dcosdri,dri,dri);
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vec3_scaleadd(fc*gijk*ex_delr_d,rik_hat,dri,dri);
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vec3_scaleadd(-fc*gijk*ex_delr_d,rij_hat,dri,dri);
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vec3_scale(prefactor,dri,dri);
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// compute the derivative wrt Rj
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// drj = fc*gijk_d*ex_delr*dcosdrj;
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// drj += fc*gijk*ex_delr_d*rij_hat;
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vec3_scale(fc*gijk_d*ex_delr,dcosdrj,drj);
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vec3_scaleadd(fc*gijk*ex_delr_d,rij_hat,drj,drj);
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vec3_scale(prefactor,drj,drj);
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// compute the derivative wrt Rk
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// drk = dfc*gijk*ex_delr*rik_hat;
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// drk += fc*gijk_d*ex_delr*dcosdrk;
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// drk += -fc*gijk*ex_delr_d*rik_hat;
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vec3_scale(dfc*gijk*ex_delr,rik_hat,drk);
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vec3_scaleadd(fc*gijk_d*ex_delr,dcosdrk,drk,drk);
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vec3_scaleadd(-fc*gijk*ex_delr_d,rik_hat,drk,drk);
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vec3_scale(prefactor,drk,drk);
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}
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ucl_inline void ters_zetaterm_d_fi(const numtyp prefactor,
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const numtyp rij_hat[3],
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const numtyp rij,
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const numtyp rik_hat[3],
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const numtyp rik,
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const numtyp param_bigr,
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const numtyp param_bigd,
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const numtyp param_powermint,
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const numtyp param_lam3,
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const numtyp param_c,
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const numtyp param_d,
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const numtyp param_h,
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const numtyp param_gamma,
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numtyp dri[3])
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{
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numtyp gijk,gijk_d,ex_delr,ex_delr_d,fc,dfc,cos_theta,tmp;
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numtyp dcosdri[3],dcosdrj[3],dcosdrk[3];
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fc = ters_fc(rik,param_bigr,param_bigd);
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dfc = ters_fc_d(rik,param_bigr,param_bigd);
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numtyp t = param_lam3*(rij-rik);
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if ((int)param_powermint == 3) tmp = t*t*t;
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else tmp = t;
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if (tmp > (numtyp)69.0776) ex_delr = (numtyp)1.e30;
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else if (tmp < (numtyp)-69.0776) ex_delr = (numtyp)0.0;
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else ex_delr = ucl_exp(tmp);
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if ((int)param_powermint == 3)
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ex_delr_d = (numtyp)3.0*param_lam3*t*t*ex_delr;
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else ex_delr_d = param_lam3 * ex_delr;
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cos_theta = vec3_dot(rij_hat,rik_hat);
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gijk = ters_gijk(cos_theta,param_c,param_d,param_h,param_gamma);
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gijk_d = ters_gijk_d(cos_theta,param_c,param_d,param_h,param_gamma);
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costheta_d(rij_hat,rij,rik_hat,rik,dcosdri,dcosdrj,dcosdrk);
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// compute the derivative wrt Ri
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// dri = -dfc*gijk*ex_delr*rik_hat;
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// dri += fc*gijk_d*ex_delr*dcosdri;
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// dri += fc*gijk*ex_delr_d*(rik_hat - rij_hat);
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vec3_scale(-dfc*gijk*ex_delr,rik_hat,dri);
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vec3_scaleadd(fc*gijk_d*ex_delr,dcosdri,dri,dri);
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vec3_scaleadd(fc*gijk*ex_delr_d,rik_hat,dri,dri);
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vec3_scaleadd(-fc*gijk*ex_delr_d,rij_hat,dri,dri);
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vec3_scale(prefactor,dri,dri);
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}
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ucl_inline void ters_zetaterm_d_fj(const numtyp prefactor,
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const numtyp rij_hat[3],
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const numtyp rij,
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const numtyp rik_hat[3],
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const numtyp rik,
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const numtyp param_bigr,
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const numtyp param_bigd,
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const numtyp param_powermint,
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const numtyp param_lam3,
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const numtyp param_c,
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const numtyp param_d,
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const numtyp param_h,
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const numtyp param_gamma,
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numtyp drj[3])
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{
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numtyp gijk,gijk_d,ex_delr,ex_delr_d,fc,cos_theta,tmp;
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numtyp dcosdri[3],dcosdrj[3],dcosdrk[3];
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fc = ters_fc(rik,param_bigr,param_bigd);
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numtyp t = param_lam3*(rij-rik);
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if ((int)param_powermint == 3) tmp = t*t*t;
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else tmp = t;
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if (tmp > (numtyp)69.0776) ex_delr = (numtyp)1.e30;
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else if (tmp < (numtyp)-69.0776) ex_delr = (numtyp)0.0;
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else ex_delr = ucl_exp(tmp);
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if ((int)param_powermint == 3)
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ex_delr_d = (numtyp)3.0*param_lam3*t*t*ex_delr;
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else ex_delr_d = param_lam3 * ex_delr;
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cos_theta = vec3_dot(rij_hat,rik_hat);
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gijk = ters_gijk(cos_theta,param_c,param_d,param_h,param_gamma);
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gijk_d = ters_gijk_d(cos_theta,param_c,param_d,param_h,param_gamma);
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costheta_d(rij_hat,rij,rik_hat,rik,dcosdri,dcosdrj,dcosdrk);
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// compute the derivative wrt Rj
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// drj = fc*gijk_d*ex_delr*dcosdrj;
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// drj += fc*gijk*ex_delr_d*rij_hat;
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vec3_scale(fc*gijk_d*ex_delr,dcosdrj,drj);
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vec3_scaleadd(fc*gijk*ex_delr_d,rij_hat,drj,drj);
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vec3_scale(prefactor,drj,drj);
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}
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ucl_inline void ters_zetaterm_d_fk(const numtyp prefactor,
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const numtyp rij_hat[3],
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const numtyp rij,
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const numtyp rik_hat[3],
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const numtyp rik,
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const numtyp param_bigr,
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const numtyp param_bigd,
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const numtyp param_powermint,
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const numtyp param_lam3,
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const numtyp param_c,
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const numtyp param_d,
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const numtyp param_h,
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const numtyp param_gamma,
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numtyp drk[3])
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{
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numtyp gijk,gijk_d,ex_delr,ex_delr_d,fc,dfc,cos_theta,tmp;
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numtyp dcosdri[3],dcosdrj[3],dcosdrk[3];
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fc = ters_fc(rik,param_bigr,param_bigd);
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dfc = ters_fc_d(rik,param_bigr,param_bigd);
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numtyp t = param_lam3*(rij-rik);
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if ((int)param_powermint == 3) tmp = t*t*t;
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else tmp = t;
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if (tmp > (numtyp)69.0776) ex_delr = (numtyp)1.e30;
|
|
else if (tmp < (numtyp)-69.0776) ex_delr = (numtyp)0.0;
|
|
else ex_delr = ucl_exp(tmp);
|
|
|
|
if ((int)param_powermint == 3)
|
|
ex_delr_d = (numtyp)3.0*param_lam3*t*t*ex_delr;
|
|
else ex_delr_d = param_lam3 * ex_delr;
|
|
|
|
cos_theta = vec3_dot(rij_hat,rik_hat);
|
|
gijk = ters_gijk(cos_theta,param_c,param_d,param_h,param_gamma);
|
|
gijk_d = ters_gijk_d(cos_theta,param_c,param_d,param_h,param_gamma);
|
|
costheta_d(rij_hat,rij,rik_hat,rik,dcosdri,dcosdrj,dcosdrk);
|
|
|
|
// compute the derivative wrt Rk
|
|
// drk = dfc*gijk*ex_delr*rik_hat;
|
|
// drk += fc*gijk_d*ex_delr*dcosdrk;
|
|
// drk += -fc*gijk*ex_delr_d*rik_hat;
|
|
|
|
vec3_scale(dfc*gijk*ex_delr,rik_hat,drk);
|
|
vec3_scaleadd(fc*gijk_d*ex_delr,dcosdrk,drk,drk);
|
|
vec3_scaleadd(-fc*gijk*ex_delr_d,rik_hat,drk,drk);
|
|
vec3_scale(prefactor,drk,drk);
|
|
}
|
|
|
|
/* ---------------------------------------------------------------------- */
|
|
|
|
ucl_inline void repulsive(const numtyp param_bigr,
|
|
const numtyp param_bigd,
|
|
const numtyp param_lam1,
|
|
const numtyp param_biga,
|
|
const numtyp param_Z_i,
|
|
const numtyp param_Z_j,
|
|
const numtyp param_ZBLcut,
|
|
const numtyp param_ZBLexpscale,
|
|
const numtyp global_e,
|
|
const numtyp global_a_0,
|
|
const numtyp global_epsilon_0,
|
|
const numtyp rsq,
|
|
const int eflag,
|
|
numtyp *ans)
|
|
{
|
|
numtyp r,tmp_fc,tmp_fc_d,tmp_exp;
|
|
|
|
// Tersoff repulsive portion
|
|
|
|
r = ucl_sqrt(rsq);
|
|
tmp_fc = ters_fc(r,param_bigr,param_bigd);
|
|
tmp_fc_d = ters_fc_d(r,param_bigr,param_bigd);
|
|
tmp_exp = ucl_exp(-param_lam1 * r);
|
|
|
|
numtyp fforce_ters = param_biga * tmp_exp * (tmp_fc_d - tmp_fc*param_lam1);
|
|
numtyp eng_ters = tmp_fc * param_biga * tmp_exp;
|
|
|
|
// ZBL repulsive portion
|
|
|
|
numtyp esq = global_e*global_e;
|
|
numtyp a_ij = ((numtyp)0.8854*global_a_0) /
|
|
(ucl_powr(param_Z_i,(numtyp)0.23) + ucl_powr(param_Z_j,(numtyp)0.23));
|
|
numtyp premult = (param_Z_i * param_Z_j * esq)/((numtyp)4.0*MY_PI*global_epsilon_0);
|
|
numtyp r_ov_a = r/a_ij;
|
|
numtyp t1 = (numtyp)0.1818*ucl_exp((numtyp)-3.2*r_ov_a);
|
|
numtyp t2 = (numtyp)0.5099*ucl_exp((numtyp)-0.9423*r_ov_a);
|
|
numtyp t3 = (numtyp)0.2802*ucl_exp((numtyp)-0.4029*r_ov_a);
|
|
numtyp t4 = (numtyp)0.02817*ucl_exp((numtyp)-0.2016*r_ov_a);
|
|
numtyp phi = t1 + t2 + t3 + t4;
|
|
numtyp dphi = (numtyp)-3.2*t1 - (numtyp)0.9423*t2 - (numtyp)0.4029*t3 -
|
|
(numtyp)0.2016*t4;
|
|
dphi *= ucl_recip(a_ij);
|
|
/*
|
|
numtyp phi = (numtyp)0.1818*ucl_exp((numtyp)-3.2*r_ov_a) +
|
|
(numtyp)0.5099*ucl_exp((numtyp)-0.9423*r_ov_a) +
|
|
(numtyp)0.2802*ucl_exp((numtyp)-0.4029*r_ov_a) +
|
|
(numtyp)0.02817*ucl_exp((numtyp)-0.2016*r_ov_a);
|
|
numtyp dphi = ucl_recip(a_ij) * ((numtyp)-3.2*(numtyp)0.1818*ucl_exp((numtyp)-3.2*r_ov_a) -
|
|
(numtyp)0.9423*(numtyp)0.5099*ucl_exp((numtyp)-0.9423*r_ov_a) -
|
|
(numtyp)0.4029*(numtyp)0.2802*ucl_exp((numtyp)-0.4029*r_ov_a) -
|
|
(numtyp)0.2016*(numtyp)0.02817*ucl_exp((numtyp)-0.2016*r_ov_a));
|
|
*/
|
|
numtyp rinv = ucl_recip(r);
|
|
numtyp fforce_ZBL = premult*(-phi)/rsq + premult*dphi*rinv;
|
|
numtyp eng_ZBL = premult*rinv*phi;
|
|
|
|
// combine two parts with smoothing by Fermi-like function
|
|
// ans[0] = fforce
|
|
numtyp f = F_fermi(r,param_ZBLcut,param_ZBLexpscale);
|
|
numtyp f_d = F_fermi_d(r,param_ZBLcut,param_ZBLexpscale);
|
|
ans[0] = -(-f_d * eng_ZBL + ((numtyp)1.0 - f)*fforce_ZBL + f_d*eng_ters +
|
|
f*fforce_ters) * rinv;
|
|
|
|
// ans[1] = eng
|
|
if (eflag) ans[1] = ((numtyp)1.0 - f)*eng_ZBL + f*eng_ters;
|
|
}
|
|
|
|
/* ---------------------------------------------------------------------- */
|
|
|
|
ucl_inline numtyp zeta(const numtyp param_powermint,
|
|
const numtyp param_lam3,
|
|
const numtyp param_bigr,
|
|
const numtyp param_bigd,
|
|
const numtyp param_c,
|
|
const numtyp param_d,
|
|
const numtyp param_h,
|
|
const numtyp param_gamma,
|
|
const numtyp rsqij,
|
|
const numtyp rsqik,
|
|
const numtyp4 delrij,
|
|
const numtyp4 delrik)
|
|
{
|
|
numtyp rij,rik,costheta,arg,ex_delr;
|
|
|
|
rij = ucl_sqrt(rsqij);
|
|
rik = ucl_sqrt(rsqik);
|
|
costheta = (delrij.x*delrik.x + delrij.y*delrik.y +
|
|
delrij.z*delrik.z) / (rij*rik);
|
|
|
|
numtyp t = param_lam3*(rij-rik);
|
|
if ((int)param_powermint == 3) arg = t*t*t;
|
|
else arg = t;
|
|
|
|
if (arg > (numtyp)69.0776) ex_delr = (numtyp)1.e30;
|
|
else if (arg < (numtyp)-69.0776) ex_delr = (numtyp)0.0;
|
|
else ex_delr = ucl_exp(arg);
|
|
|
|
return ters_fc(rik,param_bigr,param_bigd) *
|
|
ters_gijk(costheta,param_c, param_d, param_h, param_gamma) * ex_delr;
|
|
}
|
|
|
|
/* ---------------------------------------------------------------------- */
|
|
|
|
ucl_inline void force_zeta(const numtyp param_bigb,
|
|
const numtyp param_bigr,
|
|
const numtyp param_bigd,
|
|
const numtyp param_lam2,
|
|
const numtyp param_beta,
|
|
const numtyp param_powern,
|
|
const numtyp param_c1,
|
|
const numtyp param_c2,
|
|
const numtyp param_c3,
|
|
const numtyp param_c4,
|
|
const numtyp param_ZBLcut,
|
|
const numtyp param_ZBLexpscale,
|
|
const numtyp rsq,
|
|
const numtyp zeta_ij,
|
|
const int eflag,
|
|
numtyp fpfeng[4])
|
|
{
|
|
numtyp r,fa,fa_d,bij;
|
|
|
|
r = ucl_sqrt(rsq);
|
|
fa = ters_fa(r,param_bigb,param_bigr,param_bigd,param_lam2,param_ZBLcut,param_ZBLexpscale);
|
|
fa_d = ters_fa_d(r,param_bigb,param_bigr,param_bigd,param_lam2,param_ZBLcut,param_ZBLexpscale);
|
|
bij = ters_bij(zeta_ij,param_beta,param_powern,
|
|
param_c1,param_c2, param_c3, param_c4);
|
|
fpfeng[0] = (numtyp)0.5*bij*fa_d * ucl_recip(r); // fforce
|
|
fpfeng[1] = (numtyp)-0.5*fa * ters_bij_d(zeta_ij,param_beta, param_powern,
|
|
param_c1,param_c2, param_c3, param_c4); // prefactor
|
|
if (eflag) fpfeng[2] = (numtyp)0.5*bij*fa; // eng
|
|
}
|
|
|
|
/* ----------------------------------------------------------------------
|
|
attractive term
|
|
use param_ij cutoff for rij test
|
|
use param_ijk cutoff for rik test
|
|
------------------------------------------------------------------------- */
|
|
|
|
ucl_inline void attractive(const numtyp param_bigr,
|
|
const numtyp param_bigd,
|
|
const numtyp param_powermint,
|
|
const numtyp param_lam3,
|
|
const numtyp param_c,
|
|
const numtyp param_d,
|
|
const numtyp param_h,
|
|
const numtyp param_gamma,
|
|
const numtyp prefactor,
|
|
const numtyp rij,
|
|
const numtyp rijinv,
|
|
const numtyp rik,
|
|
const numtyp rikinv,
|
|
const numtyp delrij[3],
|
|
const numtyp delrik[3],
|
|
numtyp fi[3],
|
|
numtyp fj[3],
|
|
numtyp fk[3])
|
|
{
|
|
numtyp rij_hat[3],rik_hat[3];
|
|
vec3_scale(rijinv,delrij,rij_hat);
|
|
vec3_scale(rikinv,delrik,rik_hat);
|
|
ters_zetaterm_d(prefactor,rij_hat,rij,rik_hat,rik,
|
|
param_bigr, param_bigd, param_powermint, param_lam3,
|
|
param_c, param_d, param_h, param_gamma, fi, fj, fk);
|
|
}
|
|
|
|
ucl_inline void attractive_fi(const numtyp param_bigr,
|
|
const numtyp param_bigd,
|
|
const numtyp param_powermint,
|
|
const numtyp param_lam3,
|
|
const numtyp param_c,
|
|
const numtyp param_d,
|
|
const numtyp param_h,
|
|
const numtyp param_gamma,
|
|
const numtyp prefactor,
|
|
const numtyp rij,
|
|
const numtyp rijinv,
|
|
const numtyp rik,
|
|
const numtyp rikinv,
|
|
const numtyp delrij[3],
|
|
const numtyp delrik[3],
|
|
numtyp fi[3])
|
|
{
|
|
numtyp rij_hat[3],rik_hat[3];
|
|
vec3_scale(rijinv,delrij,rij_hat);
|
|
vec3_scale(rikinv,delrik,rik_hat);
|
|
ters_zetaterm_d_fi(prefactor,rij_hat,rij,rik_hat,rik,
|
|
param_bigr, param_bigd, param_powermint, param_lam3,
|
|
param_c, param_d, param_h, param_gamma, fi);
|
|
}
|
|
|
|
ucl_inline void attractive_fj(const numtyp param_bigr,
|
|
const numtyp param_bigd,
|
|
const numtyp param_powermint,
|
|
const numtyp param_lam3,
|
|
const numtyp param_c,
|
|
const numtyp param_d,
|
|
const numtyp param_h,
|
|
const numtyp param_gamma,
|
|
const numtyp prefactor,
|
|
const numtyp rij,
|
|
const numtyp rijinv,
|
|
const numtyp rik,
|
|
const numtyp rikinv,
|
|
const numtyp delrij[3],
|
|
const numtyp delrik[3],
|
|
numtyp fj[3])
|
|
{
|
|
numtyp rij_hat[3],rik_hat[3];
|
|
vec3_scale(rijinv,delrij,rij_hat);
|
|
vec3_scale(rikinv,delrik,rik_hat);
|
|
ters_zetaterm_d_fj(prefactor,rij_hat,rij,rik_hat,rik,
|
|
param_bigr, param_bigd, param_powermint, param_lam3,
|
|
param_c, param_d, param_h, param_gamma, fj);
|
|
}
|
|
|
|
ucl_inline void attractive_fk(const numtyp param_bigr,
|
|
const numtyp param_bigd,
|
|
const numtyp param_powermint,
|
|
const numtyp param_lam3,
|
|
const numtyp param_c,
|
|
const numtyp param_d,
|
|
const numtyp param_h,
|
|
const numtyp param_gamma,
|
|
const numtyp prefactor,
|
|
const numtyp rij,
|
|
const numtyp rijinv,
|
|
const numtyp rik,
|
|
const numtyp rikinv,
|
|
const numtyp delrij[3],
|
|
const numtyp delrik[3],
|
|
numtyp fk[3])
|
|
{
|
|
numtyp rij_hat[3],rik_hat[3];
|
|
vec3_scale(rijinv,delrij,rij_hat);
|
|
vec3_scale(rikinv,delrik,rik_hat);
|
|
ters_zetaterm_d_fk(prefactor,rij_hat,rij,rik_hat,rik,
|
|
param_bigr, param_bigd, param_powermint, param_lam3,
|
|
param_c, param_d, param_h, param_gamma, fk);
|
|
}
|
|
|
|
|
|
#endif
|
|
|
|
|