H2O: Difference between revisions
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== Task == | == Task == | ||
Relaxation of an <math>\mathr{H}_{2}\mathrm{O}</math> molecule. | |||
== Input == | == Input == | ||
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1.10 -1.43 0.00 T T F | 1.10 -1.43 0.00 T T F | ||
1.10 1.43 0.00 T T F | 1.10 1.43 0.00 T T F | ||
All coordinates are scaled by the factor 0.52918. | |||
=== {{TAG|INCAR}} === | === {{TAG|INCAR}} === | ||
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0 0 0 | 0 0 0 | ||
== Calculation == | |||
*Use {{TAG|PREC}}=''Normal'' (Default for VASP.5.X) | |||
= | *It is strongly urged that the energy cutoffs are set manually in the {{TAG|INCAR}} file, as it provides more control over the calculations. | ||
*For the ionic optimization the DIIS algorithm is used. This algorithm builds an approximation of the Hessian matrix and converges usually faster than the conjugate gradient algorithm. It is however recommended to set the independent degrees of freedom manually. *{{TAG|EDIFFG}} determines when to terminate the relaxation. Positive values: energy change between steps must be less than the value set by {{TAG|EDIFFG}}. Negative values: <math>|\mathbf{F}_{i}| < |EDIFFG| \forall i=1,N_{\mathrm{ions}} </math>. | |||
== Download == | == Download == | ||
Revision as of 09:54, 28 April 2017
Overview > O atom > O atom spinpolarized > O atom spinpolarized low symmetry > O dimer > CO > CO vibration > CO partial DOS > H2O >
H2O vibration > H2O molecular dynamics > Further things to try > List of tutorials
Task
Relaxation of an Failed to parse (Conversion error. Server ("cli") reported: "[INVALID]"): {\displaystyle \mathr{H}_{2}\mathrm{O}} molecule.
Input
POSCAR
H2O _2
0.52918 ! scaling parameter
15 0 0
0 15 0
0 0 15
1 2
select
cart
0.00 0.00 0.00 F F F
1.10 -1.43 0.00 T T F
1.10 1.43 0.00 T T F
All coordinates are scaled by the factor 0.52918.
INCAR
PREC = Normal ! standard precision ENMAX = 400 ! cutoff should be set manually ISMEAR = 0 ; SIGMA = 0.1 IBRION = 1 ! use DIIS algorithm to converge NFREE = 2 ! 2 independent degrees of freedom NSW = 10 ! 10 ionic steps EDIFFG = -0.02 ! forces smaller 0.02 A/eV
KPOINTS
Gamma-point only 0 Monkhorst Pack 1 1 1 0 0 0
Calculation
- Use PREC=Normal (Default for VASP.5.X)
- It is strongly urged that the energy cutoffs are set manually in the INCAR file, as it provides more control over the calculations.
- For the ionic optimization the DIIS algorithm is used. This algorithm builds an approximation of the Hessian matrix and converges usually faster than the conjugate gradient algorithm. It is however recommended to set the independent degrees of freedom manually. *EDIFFG determines when to terminate the relaxation. Positive values: energy change between steps must be less than the value set by EDIFFG. Negative values: .
Download
To the list of examples or to the main page