Cooperative and diminutive hydrogen bonding in Y...HCN...HCN and NCH...Y...HCN trimers (Y=BF,CO,N2).
A computational study of the cooperative effect of hydrogen bonding in Y...HCN...HCN and its diminutive effect in NCH...Y...HCN (Y=BF,CO,N2) linear complexes relative to the Y...HCN dimer was undertaken at the MP2/6-311++G(2d,2p) level of theory. It was found that the additional hydrogen bond in Y...HCN...HCN leads to an enhanced Y...HCN dissociation energy, extended H-C bond length, and larger redshift of the H-C stretch relative to Y...HCN, while opposite features are observed in NCH...Y...HCN. The cooperativity is diminished as the hardness of the Y atom directly bonded to the HCN molecule increases. A particularly interesting result is that the small bond contraction and blueshift associated with the H-C bond in BF...HCN is converted to a small bond extension and redshift on the formation of the BF...HCN...HCN trimer.
Department of Biological and Chemical Sciences, The University of the West Indies, Cave Hill Campus, P.O. Box 64, Bridgetown, Barbados. sacm@mail.com
Sean A C
SA
McDowell
A David
AD
Buckingham
D003198:Computer Simulation; D019281:Dimerization; D006860:Hydrogen Bonding; D006856:Hydrogen Cyanide / Q000737:chemistry*; D008956:Models, Chemical
D006856:Hydrogen Cyanide