Coupled-Cluster and Many-Body Perturbation Study of Energies, Structures, and Phonon Dispersions of Solid Hydrogen Fluoride OLASENI SODE, 1 MURAT KEC ¸ ELI, 2 SO HIRATA, 1,2 KIYOSHI YAGI 3 1 Department of Chemistry, Quantum Theory Project, The Center for Macromolecular Science and Engineering, University of Florida, Gainesville, FL 32611-8435 2 Department of Physics, Quantum Theory Project, The Center for Macromolecular Science and Engineering, University of Florida, Gainesville, FL 32611-8435 3 Department of Applied Chemistry, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan Received 3 October 2008; accepted 24 November 2008 Published online 4 February 2009 in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/qua.22022 ABSTRACT: A linear-scaling electron-correlation method based on a truncated many-body expansion of the energies of molecular crystals has been applied to solid hydrogen fluoride. The energies, structures, harmonic, and anharmonic frequencies of the infrared- and/or Raman-active vibrations, phonon dispersions, and inelastic neutron scattering (INS) of the solid have been simulated employing an infinite, periodic, one- dimensional zigzag hydrogen-bonded chain model. The Hartree–Fock, second-order Møller–Plesset (MP2), coupled-cluster singles and doubles (CCSD), and CCSD with a noniterative triples correction [CCSD(T)] methods have been combined with the aug-cc- pVDZ and aug-cc-pVTZ basis sets and, in some instances, the counterpoise corrections of the basis-set superposition errors. The computed structural parameters agree with the observed within 0.1– 0.2 Å and a few degrees, and the anharmonic frequencies obtained by vibrational MP2 allowing two-phonon couplings reproduce the observed frequencies Correspondence to: S. Hirata; e-mail: hirata@qtp.ufl.edu Dedicated to Professor Kimihiko Hirao on the occasion of his retirement from The University of Tokyo. Contract grant sponsor: U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Contract grant number: DE-FG02-04ER15621. Contract grant sponsor: Donors of the American Chemical Society Petroleum Research Fund. Contract grant number: 48440-AC6. International Journal of Quantum Chemistry, Vol 109, 1928 –1939 (2009) © 2009 Wiley Periodicals, Inc.