Measurement of inter- and intramolecular charge transfer in the complex N-2 center dot center dot center dot ICI from analysis of halogen nuclear quadrupole hyperfine structure in the rotational spectrum

The ground-state rotational spectra of two isotopomers N-15(2)... (ICl)-Cl- 35 and N-15(2)... (ICl)-Cl-37 of a complex formed between dinitrogen and io dine monochloride were observed by pulsed-jet, Fourier-transform microwave spectroscopy. The spectra were inter preted on the basis of a linear equili brium geometry with the weak bond formed between N and I. The spectroscopic constants B-0, D-J, chi(aa)(I), chi(aa)(Cl) and M-bb(I) were determined fo r each isotopomer and various models for the complex were employed to yield the distance r(N ... I)= 3.180(2) Angstrom, the intermolecular stretching force constant k(sigma) = 5.37(3)N m(-1), and the inter- and intramolecular electronic transfers delta(i) = 0.004(3) and delta(p)(Cl) = 0.018(2). (C) 2000 Elsevier Science B.V. All rights reserved.