At and mol further: Difference between revisions
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*Calculate the vibrational frequencies of the <math>\mathrm{H}_{2}\mathrm{O}</math> molecule (example {{TAG|H2O}}) after relaxation (example {{TAG|H2Ovib}}). Why does one find 3 modes that have small frequencies? Try {{TAG|EDIFF}}=1E-5 instead of {{TAG|EDIFF}}=1E-4. | *Calculate the vibrational frequencies of the <math>\mathrm{H}_{2}\mathrm{O}</math> molecule (example {{TAG|H2O}}) after relaxation (example {{TAG|H2Ovib}}). Why does one find 3 modes that have small frequencies? Try {{TAG|EDIFF}}=1E-5 instead of {{TAG|EDIFF}}=1E-4. | ||
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Back to the [[:Category:Tutorials |list of tutorials]] or to the [[The_VASP_Manual|main page]] | |||
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Revision as of 15:14, 9 August 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
- How does the energy change when one decreases SIGMA to 0.001 in the INCAR file starting from the O_atom? Why?
- What is the reason for the imaginary frequency in the example CO_vibration? Does the behaviour improve when the step width (smaller or larger) is changed? Also try to improve the precision to which the ground state is converged (EDIFF=1E-5). What happens if the accuracy of the calculations is improved (PREC=Accurate}}).
- Try to use the conjugate gradient algorithm to the molecule (example H2O).
- Calculate the vibrational frequencies of the molecule (example H2O) after relaxation (example H2Ovib). Why does one find 3 modes that have small frequencies? Try EDIFF=1E-5 instead of EDIFF=1E-4.
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
Back to the list of tutorials or to the main page