K. Hinds et al., ROTATIONAL SPECTRUM AND PROPERTIES OF A COMPLEX OF HYDROGEN-CYANIDE AND CHLORINE MONOFLUORIDE, Molecular physics, 88(3), 1996, pp. 673-682
Rotational spectra of the five isotopomers (HCN)-N-14 ...(ClF)-Cl-35,
(HCN)-N-14 ...(ClF)-Cl-37, (DCN)-N-14 ...(ClF)-Cl-35, (HCN)-N-15 ...(C
lF)-Cl-35,, and (HCN)-N-15 ...(ClF)-Cl-37 of a complex of hydrogen cya
nide and chlorine monofluoride were observed with a pulsed nozzle, Fou
rier transform microwave spectrometer. The component gases were brough
t together in a fast-mixing nozzle to preclude mutual chemical reactio
n. Groundstate spectroscopic constants B-0, D-J, chi(aa)(N-14), chi(aa
)(Cl) and M(bb)(Cl) are reported. Interpretation of the spectroscopic
constants with the aid of various models has led to the conclusions th
at HCN ... ClF is a linear molecule with nuclei in the order shown, th
at when HCN achieves its equilibrium position in the complex the elect
ric perturbation of ClF is equivalent to a migration of a fraction del
ta approximate to 0.04 of an electronic charge from Cl to F, and that
the complex is weakly bound according to the magnitude (k(sigma) = 12.
3 N m(-1)) of the intermolecular stretching force constant. From a com
parison of the family of complexes HCN ... XY, where XY = ClF, BrCl an
d Cl-2, it is concluded that all three can be described as Mulliken co
mplexes of the weak, outer type.