A monomeric complex of ammonia and cuprous chloride: H3N••CuCl isolated and characterised by rotational spectroscopy and ab initio calculations

The H3N center dot center dot center dot CuCl monomer has been generated and isolated in the gas phase through laser vaporisation of a copper sample in the presence of low concentrations of NH3 and CCl4 in argon. The resulting complex cools to a rotational temperature approaching 2 K during supersonic expansion of the gas sample and is characterised by broadband rotational spectroscopy between 7 and 18.5 GHz. The spectra of six isotopologues are measured and analysed to determine rotational, B-0; centrifugal distortion, D-J, D-JK; and nuclear quadrupole coupling constants of Cu, Cl, and N-14 nuclei, chi(aa)(X). The geometry of the complex is C-3v with the N, Cu, and Cl atoms located on the a inertial axis. Bond distances and the angle(H-N center dot center dot center dot Cu) bond angle within the complex are precisely evaluated through fitting of geometrical parameters to the experimentally determined moments of inertia and through ab initio calculations at the CCSD(T)(F12*)/AVQZ level. The r(Cu-Cl), r(Cu-N), and angle(H-N center dot center dot center dot Cu) parameters are, respectively, evaluated to be 2.0614(7) angstrom, 1.9182(13) angstrom, and 111.40(6)degrees in the r(0) geometry, in good agreement with the ab initio calculations. Geometrical parameters evaluated for the isolated complex are compared with those established crystallographically for a solid-state sample of [Cu(NH3)Cl]. (C) 2015 AIP Publishing LLC.