Articles tagged with: solid state

Convert CPMD TRAJECTORY for tfreq Autocorrelation and Vibrational Density of States

May 26, 2011

Recently, I’ve been getting a few of people wanting to use tfreq, autocorrelation and vibrational density of states to analyse data from CPMD. tfreq is written to process output from Quantum-ESPRESSO‘s cp.x output. The two options are to modify the source file tfreq.c to read the new input, which could be difficult for someone inexperienced […]

Velocity Autocorrelation and Vibrational Spectrum Calculation

September 29, 2010

The velocity autocorrelation function (VAF) is usually calculated when one wishes to analyse the vibrational or diffusive properties of a system of atoms. [...] If the motion of the atoms tends to an oscillatory pattern, the VAF will characterize the ossilations because the velocity of the atoms will self-correlate in a periodic fashion…