Natural bond orbital analysis of molecular interactions: Theoretical studies of binary complexes of HF, H/sub 2/O, NH/sub 3/, N/sub 2/, O/sub 2/, F/sub 2/, CO, and CO/sub 2/ with HF, H/sub 2/O, and NH/sub 3/

Journal Article · Thu May 15 04:00:00 EDT 1986 · J. Chem. Phys.; (United States)

OSTI ID:5742794

Reed, A E; Weinhold, F; Curtiss, L A; Pochatko, D J

The binary complexes of HF, H/sub 2/O, NH/sub 3/, N/sub 2/, O/sub 2/, F/sub 2/, CO, and CO/sub 2/ with HF, H/sub 2/O, and NH/sub 3/ have been studied by ab initio molecular orbital theory and natural bond orbital (NBO) analysis. Most of the complexes involving N/sub 2/, O/sub 2/, F/sub 2/, CO, and CO/sub 2/ are found to have both hydrogen-bonded and non-hydrogen-bonded structures. The NBO analysis provides a consistent picture of the bonding in this entire family of complexes in terms of charge transfer (CT) interactions, showing the close correlation of these interactions with the van der Waals penetration distance and dissociation energy of the complex. Contrary to previous studies based on the Kitaura--Morokuma analysis, we find a clear theoretical distinction between H-bonded and non-H-bonded complexes based on the strength of CT interactions. Charge transfer is generally stronger in H-bonded than in non-H-bonded complexes. It plays an intermediate role in non-H-bonded CO/sub 2/ complexes which have been studied experimentally. However, the internal rotation barrier (1 kcal mol/sup -1/) of the H/sub 2/OxxxCO/sub 2/ complex is found to be primarily of electrostatic origin with only a small (..pi..-type) CT contribution. The role of electrostatic interactions, effect of electron correlation, and comparison of theory with experiment are also discussed.

• Research Organization: Theoretical Chemistry Institute and Deparment of Chemistry, University of Wisconsin, Madison, Wisconsin 53706
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5742794
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 84:10; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ADDUCTS
AMMONIA
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CHARGE EXCHANGE
CHEMICAL BONDS
COMPLEXES
CORRELATIONS
ELECTRON CORRELATION
ELECTRONIC STRUCTURE
ELEMENTS
FLUORINE
HALOGENS
HYDRIDES
HYDROFLUORIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
INTERACTIONS
MOLECULAR ORBITAL METHOD
NITROGEN
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NONMETALS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
WATER