A projection method is described for elimination of spurious contributions to calculated cartesian force constants which give rise to non-zero frequencies for translational and rotational modes and which may cause errors in vibrational frequencies. Illustrative calculations for water monomer (in STO-3G) and water dimer (in 4-31G) are discussed. The preference for deuterium-bonded versus hydrogen-bonded isotopomeric water -dimer structures is demonstrated by calculations which satisfy the Teller-Redlich product rule provided that projected force constants are employed.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry