Vibrational frequencies and intensities of H‐bonded systems. 1:1 and 1:2 complexes of NH3 and PH3 with HF

Content Provider	Semantic Scholar
Author	Kurnig, Ingrid J. Szczęśniak, Małgorzata M. Scheiner, Steve
Copyright Year	1987
Abstract	Frequencies and intensities are calculated by ab initio methods for all vibrational modes of the 1:1 H3X–HF and 1:2 H3X–HF–HF complexes (X=N,P). The HF stretching frequencies are subject to red shifts, roughly proportional to the strength of the H bond, and to manyfold increases in intensity. Although the intramolecular frequency shifts within the proton acceptors are relatively modest, the intensities of the NH3 stretches are magnified by several orders of magnitude as a result of H bonding (in contrast to PH3 which exhibits little sensitivity in this regard). The frequencies and intensities corresponding to bending of the H3X–HF H‐bond rise with increasing H‐bond strength while the properties of the other intermolecular modes appear somewhat anomalous at first sight. The intensity patterns are analyzed by means of atomic polar tensors which reveal that intensification of the proton donor stretch is chiefly due to increasing charge flux associated with H‐bond formation. The different behavior of the N–H ...
Starting Page	2214
Ending Page	2224
Page Count	11
File Format	PDF HTM / HTML
DOI	10.1063/1.453148
Volume Number	87
Alternate Webpage(s)	https://works.bepress.com/steve_scheiner/249/download/
Alternate Webpage(s)	https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1066&context=chem_facpub
Alternate Webpage(s)	https://doi.org/10.1063/1.453148
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article