Matrix Isolation Infrared Spectroscopic and Density Functional Theory Study of the 1:1 Complex of Bromocyclohexane with NH3: Evidence for a Weak C-H-N Hydrogen Bond
Kyle R. Hess: student co-author.
The hydrogen-bonded bromocyclohexane–ammonia complex has been isolated and characterized for the first time in argon matrices at 16 K. Coordination of the proton adjacent to the Br substituent on the cyclo-hexane ring to the amino nitrogen was evidenced by distinct blue shifts of bending modes involving the H-C1-Br unit. In particular, C-C1-Br, H-C1-Br, and C-C1-H bending modes produced blue shifts ranging from 2.8 to 12.2 cm1. Density Functional Theory (DFT) calculations at the B3LYP=6–31+G(d, p) level yield an essentially linear Br-C1-H–NH3 hydrogen bond with a C-H–N distance of 2.412 Å and a hydrogen bond energy of 2.95 kcal=mol.
Hess, Kyle R., and Cindy Samet. "Matrix Isolation Infrared Spectroscopic and Density Functional Theory Study of the 1:1 Complex of Bromocyclohexane with NH3: Evidence for a Weak C-H-N Hydrogen Bond." Spectroscopy Letters 41 (2008): 179-188.