The complexes between C20 and C2 X4 , C2 X2 (X = H, F, Cl, Br) have been studied theoretically at the B3LYP/6-311G (d,p) level. The calculations include the optimized geometries, the interaction energies, aromaticity and thermodynamic. The interaction energies ranging from -60 to -101 kcal/mol and being ordered as: X = F> Cl > Br. Natural bond orbital (NBO) analysis has been performed on all ge...

Photoreaction of zinc methyl 20-substituted meso(pyro)pheophorbide-a prepared by modifying naturally occurring chlorophyll-a in the presence of oxygen molecules gave its C19-C20 oxidative cleavage (1-carbonyl-19-oxo-bilatrienes) as the major products and the regioisomeric C1-C20 cleavage (19-carbonyl-1-oxo-bilatrienes) as the minor products. The resulting zinc complexes of linear tetrapyrroles ...

An atom trapped in a crystal vacancy, metal cage, or fullerene might have many immediate neighbors. Then, the familiar concept of valency even coordination number seems inadequate to describe environment that atom. This difficulty terminology is illustrated here by four systems: H atoms tetragonal-pyramidal rhodium cages, an octahedral cobalt MgO hole, and C20 fullerenes. Density functional the...

Golden fullerenes have recently been identified by photoelectron spectra by Bulusu et al. [S. Bulusu, X. Li, L.-S. Wang, X. C. Zeng, PNAS 2006, 103, 8326-8330]. These unique triangulations of a sphere are related to fullerene duals having exactly 12 vertices of degree five, and the icosahedral hollow gold cages previously postulated are related to the Goldberg-Coxeter transforms of C20 starting...

The structural and electronic properties of C24-2nBn Nn and M@ C24-2nBn Nn (M= alkaline and earth alkaline metals; n=3 and 6) molecules are studied using the Density Functional Theory (DFT). It was found that the most interaction is in M@ C24-2nBn Nn complexes (M=Be, Mg; n=3 and 6). The negative nucleus-independent chemical shifts confirm that C24-2nBn Nn (n=3 and 6) cages exhibit aromatic char...

Selective formation of bimetallic group 10 complexes using the Cs symmetric, bicyclic diphosphane P2C12H20 is reported herein. With its eclipsed lone pairs disposed at a relative angle of ca. 45 , the diphosphane framework is ideally suited to form multiple bridges between two metal centers. The complexes contain {M2P6} cages with three diphosphane bridges and a pair of trans-axial ligands such...

Enantiomeric M4L4 helical cages have been prepared whose supramolecular chirality is induced by the chemical chirality of the self-sorting amino acid-derived ligands that are used. Using scrambled diastereomeric ligands or achiral glycine-derived ligands yields analogous complexes yet 'turns off' the supramolecular chirality by producing centrosymmetric cages.

High-nuclearity Mn complexes have attracted significant scientific attention due to their fascinating magnetic properties and relevance bioinorganic systems catalysis. In this work, we demonstrate how the strong binding characteristics of phosphonate ligands can be coupled with sterically hindered carboxylate groups influence symmetry coordination clusters. We describe structure two high-nuclea...