12 research outputs found
Towards the chemical control of molecular packing: syntheses and crystal structures of three trans-[NiL4(NCS)2] complexes
Three nickel(II) isothiocyanato complexes of the formula
trans-[NiL4(NCS)2] (L = ethylisonicotinate, methylisonicotinate
and 4-benzoylpyridine) have been prepared: [Ni(ethylisonicotinate)
4(NCS)2] (I), [Ni(methylisonicotinate)4(NCS)2]
(II) and [Ni(4-benzoylpyridine)4(NCS)2] (III). All three
complexes are monomeric and have a distorted octahedral
geometry around NiII. Despite their apparent molecular
similarity, the crystal density of (III) (1.454 g cm 3) is
significantly higher than that of (I) and (II) (both
1.408 g cm 3), suggesting that the molecular packing is most
efficient in (III). A study of the molecular Hirshfeld surfaces,
together with density functional theory (DFT) calculations,
provide insights into the origin of the molecular packing
features, and it is suggested that the greater crystal density of
(III) results from smaller intermolecular electrostatic repulsions
Interpretation of the terminal v(co) spectra of some M5 transition metal carbonyl clusters
The n(CO) spectra of 31 M5 transition metal carbonyl clusters are interpreted in terms of the spherical harmonic and tensor harmonic models. It seems that the former is that which is generally applicable but that the splittings of the (spherical) P mode are larger than had previously been considered indicative of this model. An explanation in terms of the cluster asymmetry is suggested