Ab initio molecular dynamics of liquid water using embedded-fragment second-order many-body perturbation theory towards its accurate property prediction

• DOI: 10.1038/srep14358
• Publication Date: 2015-09-24T08:45:56Z
• Authors: Soohaeng Yoo Willow; Michael A. Salim; Kwang S. Kim; So Hirata
• Keywords: Water dimer; Coupled cluster

Abstract A direct, simultaneous calculation of properties a liquid using an ab initio electron-correlated theory has long been unthinkable. Here we present structural, dynamical and response water calculated by molecular dynamics the embedded-fragment spin-component-scaled second-order many-body perturbation method with aug-cc-pVDZ basis set. This level is chosen as it accurately inexpensively reproduces dimer potential energy surface from coupled-cluster singles, doubles noniterative triples aug-cc-pVQZ set, which nearly exact. The radial distribution function, self-diffusion coefficient, coordinate number dipole moment, well infrared Raman spectra are in excellent agreement experimental results. shapes widths OH stretching bands their isotropic-anisotropic noncoincidence, reflect diverse local hydrogen-bond environment, also reproduced computationally. simulation reveals intriguing dynamic features difficult to probe experimentally, such surprisingly large fluctuation coordination detailed mechanism hydrogen donating molecules move across first second shells, thereby causing this fluctuation.