A comparative study of some red- and blue-shifted linear H-bonded complexes of N2

✍ Scribed by Sean A. C. McDowell

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 138 KB
• Volume: 29
• Category: Article
• ISSN: 0192-8651
• DOI: 10.1002/jcc.20792

✦ Synopsis

Abstract

Bond length changes, harmonic vibrational frequency shifts, and changes in the proton magnetic shielding of HX and HKrX (X = F, Cl) on complexation with N~2~ to form the linear red‐shifted N~2~ … HX and linear blue‐shifted N~2~ … HKrX complexes were determined by ab initio computations, with and without counterpoise correction, at the SCF and MP2(full) levels of theory using a 6‐311++G(2d,2p) basis set. The MP2 computations agree with predictions from a perturbation theory model involving the first and second derivatives of the interaction energy with respect to displacement of the HX and HKr bond lengths from their equilibrium values in the isolated monomers. The theoretical results agree qualitatively with the experimentally observed frequency shifts, with near quantitative agreement for N~2~ … HKrCl. The characteristic downfield shift of the isotropic proton magnetic resonance in the red‐shifted complexes was obtained, but for the blue‐shifted complexes, the proton NMR shifts to higher fields. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008