title: Assignment of the vibrational spectra of lithium hydroxide monohydrate, LiOH·H2O.
abstract: The assignment of the vibrational spectra of lithium hydroxide monohydrate, LiOH·H(2)O, has been controversial for more than half-a-century. Here we show that only the combination of all three forms of vibrational spectroscopy: infrared, Raman and inelastic neutron scattering spectroscopies coupled with periodic-density functional theory calculations is able to satisfactorily assign the spectra. All previous work based on empirical criteria is, at least partially, incorrect. The librational modes of water do not follow the expected rock > wag > twist order and the calculations indicate that complete or partial deuterium substitution would not be useful in assigning the modes.
authors.affiliation: ISIS Facility, STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, United Kingdom. stewart.parker@stfc.ac.uk
authors.forename: Stewart F
authors.initials: SF
authors.lastname: Parker
authors.forename: Keith
authors.initials: K
authors.lastname: Refson
authors.forename: Robert I
authors.initials: RI
authors.lastname: Bewley
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Dent
mesh_terms: D018020:Lithium Compounds / Q000737:chemistry*; D008958:Models, Molecular; D011789:Quantum Theory; D013055:Spectrophotometry, Infrared; D013059:Spectrum Analysis, Raman; D014867:Water / Q000737:chemistry*
chemical_list: D018020:Lithium Compounds; D014867:Water; C028467:lithium hydroxide