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Added README files to subdirectories 

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Disclaimer: Using these force fields for systems they
have not been explicitly trained against may produce
unrealistic results. Please see the README file in
each subdirectory for more detailed information.
Ammonia Borane:
The follow information is reproduced from:
"Weismiller, M.R.; van Duin, A.C.T.; Lee, J.;
Yetter, R.A. J. Phys. Chem. A 2010, 114, 5485-5492"
- QM data were generated describing the single and
(if relevant) double and triple bond dissociation
for all B/N/O/H combinations. These data were used
to derive initial ReaxFF bond parameters, and all
calculations were performed using DFT with the B3LYP
functional and the Pople 6-311G** basis set.
- The training set was then extended with QM data
describing angular distortions in a set of small
AB-related (AB = H3N-BH3) molecules. These data
were used to derive the initial ReaxFF angular
parameters.
- The training set was extended with reaction barriers
for key reaction steps such as H2 release
from AB, dimerization of H2B-NH2 and reaction
energies associated with H2 release from AB and with AB
oxidation.

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Disclaimer: Using these force fields for systems they
have not been explicitly trained against may produce
unrealistic results. Please see the README file in
each subdirectory for more detailed information.
Au/O
The follow information is reproduced from
"Keith, J. A.; Fantauzzi, D.; Jacob, T.;
van Duin, A. C. T. Phys Rev B 2010, 81, 235404"
- The force field optimization involved parameterization
of the fcc, bcc, ideal-hcp, sc, diamond, and a15 bulk phases of Au.
For these phases the ReaxFF force field gives good
agreement for the binding energy, volume of minimum
energy, and curvature of the binding well around the
minimum compared to the QM calculations used
for parameterization.

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Disclaimer: Using these force fields for systems they
have not been explicitly trained against may produce
unrealistic results. Please see the README file in
each subdirectory for more detailed information.
Hydrocarbon oxidation C/H/O:
The follow information is reproduced from:
"Chenoweth, K.; van Duin, A.C.T.; Goddard, W.A.
J. Phys. Chem. A 2008, 112, 1040-1053."
- To obtain the H/C/O compound data required to
extend the hydrocarbon-training set, DFT
calculations were performed on the following systems:
(a) dissociation energies for various bonds
containing carbon, oxygen, and hydrogen. The
ground state structure was obtained through
full geometry optimization. Dissociation curves
were calculated by constraining only the bond length of
interest and re-optimization of the remaining
internal coordinates. Optimization was also performed
for the various angles and torsions associated
with C/H/O interactions.

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Disclaimer: Using these force fields for systems they
have not been explicitly trained against may produce
unrealistic results. Please see the README file in
each subdirectory for more detailed information.
Fe/O/H
The follow information is reproduced from:
"Aryanpour, M.; van Duin, A. C. T.; Kubicki,
J. D. J. Phys. Chem. A 2010, 114, 6298-6307"
- The initial force field parameters for the
Fe-Fe parameters were taken from an
earlier force field development
project on bulk-iron metal, based on
DFT-calculations on antiferromagnetic
BCC and FCC. The DFT data can
be found in Ref 31 of the above-mentioned manuscript.
The O/H parameters were taken from the ReaxFF bulk
water description. The Fe/Fe and O/H parameters were
kept fixed to these initial values,
whereas the Fe/O parameters were reoptimized
against the quantum mechanical results
presented in the above-mentioned manuscript.
- Detailed information on the force field parameters
is given in the supporting information of the above mentioned
manuscript.

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Disclaimer: Using these force fields for systems they
have not been explicitly trained against may produce
unrealistic results. Please see the README file in
each subdirectory for more detailed information.
RDX/High Energy C/H/O/N:
The follow information is reproduced from:
"Strachan, A.; van Duin, A. C. T.; Chakraborty, D.;
Dasgupta, S.; Goddard III, W. A. Phys. Rev. Lett.
2003, 91, 098301"
"Strachan, A.; Kober, E.; van Duin, A. C. T.;
Oxgaard, J.; Goddard III, W. A. J. Chem. Phys.
2005, 122, 054502"
"Zhang, L.; van Duin, A.C.T.; Zybin, S.;
Goddard, W.A. J. Phys. Chem. B 2009, 113, 10770-10778"
"Zhang, L.; Zybin, S.; van Duin, A.C.T.; Dasgupta, S.;
Goddard, W.A.; Kober, E. J. Phys. Chem. A. 2009,
113, 10619-10640"
- The parameters of the nitramine ReaxFF are based
on a large number of ab initio QM calculations.
Over 40 reactions and over 1600 equilibrated molecules
have been used; they are designed to characterize
the atomic interactions under various environments
likely and unlikely high energy each atom can encounter.
The training set contains bond breaking and compression
curves for all possible bonds, angle and torsion bending
data for all possible cases, as well as crystal
data.
- Please see the supplemental material from
Phys. Rev. Lett. 2003, 91, 098301
for a detailed description of the
parameterization of this force field.

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examples/reax/README
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@ -9,16 +9,21 @@ contains validated parameter files for a particular
published version of ReaxFF. In all cases, the examples
use pair_style reax/c.
AB: Reactive MD-force field for Ammonia Borane: Weismiller, M.R.; van Duin, A.C.T.; Lee, J.; Yetter, R.A. J. Phys. Chem. A 2010, 114, 5485-5492
Disclaimer: Using these force fields for systems they
have not been explicitly trained against may produce
unrealistic results. Please see the README file in
each subdirectory for more detailed information.
Au_O: Reactive MD-force field: Au-Au: Keith, J. A. et al. Phys Rev B 2010, 81, 235404; Joshi, K. et al., J. Mat. Chem 2010, 20, 10431-10437
AB (Ammonia Borane): Weismiller, M.R.; van Duin, A.C.T.; Lee, J.; Yetter, R.A. J. Phys. Chem. A 2010, 114, 5485-5492
CHO: Reactive MD-force field c/h/o combustion force field: Chenoweth, K.; van Duin, A.C.T.; Goddard, W.A. J. Phys. Chem. A 2008, 112, 1040-1053.
Au_O (Gold-Oxygen): Keith, J. A. et al. Phys Rev B 2010, 81, 235404; Joshi, K. et al., J. Mat. Chem 2010, 20, 10431-10437
Fe_O_C_H: Reactive MD-force field: Fe/O/water: Aryanpour, M.; van Duin, A. C. T.; Kubicki, J. D. J. Phys. Chem. A 2010, 114, 6298-6307
CHO (C/H/O combustion): Chenoweth, K.; van Duin, A.C.T.; Goddard, W.A. J. Phys. Chem. A 2008, 112, 1040-1053.
RDX: Reactive MD-force field nitramines (RDX/HMX/TATB/PETN): Strachan, A.; et al. Phys. Rev. Lett. 2003, 91, 098301
Fe_O_C_H (Fe/O/water): Aryanpour, M.; van Duin, A. C. T.; Kubicki, J. D. J. Phys. Chem. A 2010, 114, 6298-6307
V_O_H: Reactive MD-force field: V/O/C/H potential: Chenoweth, K.; et al. J. Phys. Chem. C, 2008, 112, 14645-14654.
RDX (Nitramines RDX/HMX/TATB/PETN): Strachan, A.; et al. Phys. Rev. Lett. 2003, 91, 098301
Zn_O_H: Reactive MD-force field: water/zinc: Raymand, D.; van Duin A.C.T.; Baudin M.; Hermannson K. Surface Science 2008, 602, 1020-1031.
V_O_H (Vanadium V/O/C/H potential): Chenoweth, K.; et al. J. Phys. Chem. C, 2008, 112, 14645-14654.
Zn_O_H (Water/Zinc): Raymand, D.; van Duin A.C.T.; Baudin M.; Hermannson K. Surface Science 2008, 602, 1020-1031.

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Disclaimer: Using these force fields for systems they
have not been explicitly trained against may produce
unrealistic results. Please see the README file in
each subdirectory for more detailed information.
V/O
The follow information is reproduced from:
"Chenoweth, K.; van Duin A.C.T.; Persson, P.;
Cheng M.J.; Oxgaard, J.; Goddard W.A.
J. Phys. Chem. C, 2008, 112, 14645-14654."
- The ReaxFF force field parameters have been fit
to a large quantum mechanics (QM) training set containing over 700
structures and energetics related to bond dissociations, angle
and dihedral distortions, and reactions between hydrocarbons
and vanadium oxide clusters. In addition, the training set
contains charge distributions for small vanadium oxide clusters
and the stabilities of condensed-phase systems
including V2O5, VO2, and V2O3 in addition to metallic V (V0).

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Disclaimer: Using these force fields for systems they
have not been explicitly trained against may produce
unrealistic results. Please see the README file in
each subdirectory for more detailed information.
Zn/O/H:
The follow information is reproduced from:
"Raymand, D.; van Duin A.C.T.; Baudin M.; Hermannson K.
Surface Science 2008, 602, 1020-1031."
"Raymand, D.; van Duin, A. C. T.; Spangberg, D.;
Goddard, W. A.; Hermansson, K. Surface Science
2010, 604, 9-10, 741-752."
- Based on QM calculations for Zn(s), ZnO(s),
and Zn hydroxide clusters [Zn(OH)2 and O(ZnOH)2],
ReaxFF parameters were generated for Zn-O and
Zn-Zn bond energies and for Zn-O-Zn, O-Zn-O,
O-Zn-Zn and Zn-O-H valence angle energies.
- QM calculations were performed for the four
crystal polymorphs of the wurtzite, zincblende,
rocksalt and caesium chloride structures
(the structures are also referred to as h-ZnS,
c-ZnS, NaCl and CsCl, respectively).