COPPER-63,65 NUCLEAR-QUADRUPOLE RESONANCE STUDIES OF COPPER(I) COMPLEXES WITH SULFUR-CONTAINING LIGANDS .2. BIS (1-ALKYLIMIDAZOLIDINE-2-THIONE)COPPER(I) IODIDES AND RELATED-COMPOUNDS
S. Ramaprabhu et al., COPPER-63,65 NUCLEAR-QUADRUPOLE RESONANCE STUDIES OF COPPER(I) COMPLEXES WITH SULFUR-CONTAINING LIGANDS .2. BIS (1-ALKYLIMIDAZOLIDINE-2-THIONE)COPPER(I) IODIDES AND RELATED-COMPOUNDS, Journal of the Chemical Society. Dalton transactions, (8), 1993, pp. 1185-1190
The Cu-63 NQR resonances frequencies of ten three-co-ordinated copper(
I) complexes, in each of which at least two of the ligands are thiones
, have been determined. The Zeeman splitting of the Cu-63 NQR spectrum
of a single crystal of bis(tetrahydro-1 H-pyrimidine-2-thione)copper(
I) chloride yields the value of 0.36(2) for the asymmetry parameter wi
th the field-gradient z axis perpendicular to the CuS2Cl plane and the
y axis along the Cu-Cl bond. The crystal structure of a representativ
e member of these complexes, bis(1-propyl-imidazolidine-2-thione)coppe
r(I) iodide, confirms the three-co-ordination of the Cu(I). When one o
f the ligands is a halogen atom the results confirm the previously rep
orted trend that, for a given ligand, the Cu-63 NQR resonance frequenc
ies of the complexes [CuL2X] are in the order Cl > Br > 1. For two of
the complexes the temperature dependence of the NQR frequency indicate
s that a phase change occurs in the range 77-300 K.