Jump to main content
Jump to site search


Which quantum statistics–classical dynamics method is best for water?

Author affiliations

Abstract

There are a variety of methods for including nuclear quantum effects in dynamics simulations by combining quantum Boltzmann statistics with classical dynamics. Among them are thermostatted ring-polymer molecular dynamics (TRPMD), centroid molecular dynamics (CMD), quasi-centroid molecular dynamics (QCMD), and the linearised semi-classical initial value representation (LSC-IVR). Here we make a systematic comparison of these methods by calculating the infrared spectrum of water in the gas phase, and in the liquid and ice phases (using the q-TIP4P/F model potential). Some of these results are taken from previous work, and some of them are new (including the LSC-IVR calculations for ice, and extensions of all the spectra into the near-infrared region dominated by overtone and combination bands). Our results suggest that QCMD is the best method for reproducing fundamental transitions in the spectrum, and that LSC-IVR gives the best overall description of the spectrum (albeit with large errors in the bend fundamental band caused by zero-point-energy leakage). The TRPMD method gives damped spectra that line up with the QCMD spectra, and is by far the cheapest method.

Graphical abstract: Which quantum statistics–classical dynamics method is best for water?

Back to tab navigation

Publication details

The article was received on 03 Jun 2019, accepted on 14 Jun 2019 and first published on 15 Jun 2019


Article type: Paper
DOI: 10.1039/C9FD00077A
Faraday Discuss., 2019, Advance Article

  •   Request permissions

    Which quantum statistics–classical dynamics method is best for water?

    R. L. Benson, G. Trenins and S. C. Althorpe, Faraday Discuss., 2019, Advance Article , DOI: 10.1039/C9FD00077A

Search articles by author

Spotlight

Advertisements