Aqueous M 3+ /M 2+ redox potentials for nine of the ten fourth-period transition metals, M, have been calculated with the use of DFT methodology in combination with the COSMO continuum model. Entropy contributions to the potentials are taken from experiments. The model introduces no adjustable parameters beyond those present in the underlying theoretical models. Inclusion of two solvation spheres (18 water molecules) is necessary. For the ions studied, the average absolute difference from experimental values is 0.29 V, with four out of nine potentials (those of V, Cr, Fe, Cu) reproduced with better than 0.1 V accuracy.

The title species with the central atoms C, N, O, P, and S and up to six −AuPH3 ligands were studied at the MP2 level using effective core potentials. Structural parameters of the experimental systems were reproduced well. Two different ways of estimating the intramolecular gold−gold interaction energy from the calculated total energies are proposed, and the calculated interaction energies are found to correlate with the gold−gold distances in the systems. A giant proton binding energy of 1213 kJ/mol is calculated for the C 4 v species [HC(AuPH3)4]+.

Enantiomerically pure cyclohexylhemicucurbit[8]uril (cycHC[8]), possessing a barrel-shaped cavity, has been prepared in high yield on a gram scale from either (R,R,N,N')-cyclohex-1,2-diylurea and formaldehyde or cycHC[6]. In either case, a dynamic covalent library is first generated from which the desired cycHC can be amplified using a suitable anion template.

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Ab initio calculations of MoN2, MoP2, Mo WN2, WP2, and W were performed using quasi-relativistic effective core potentials and MP2, B3LYP, CCSD(T) and CASPT2 methodologies. Multiple local minima were found on the potential energy surfaces of the various spin states of the nitrides and phosphides. The nitrides all are either above the dissociation limit or only very slightly below it. The phosphides are energetically below the dissociation limit. The bond angles of the oxoions, as well as the phosphides and nitrides at some spin states, are nearly tetrahedral. Several minima with narrow (35−65°) bond angles, representing a side-on bond of a partially dissociated N2 or P2 molecule to the metal atom, were found as well. The oxoions and phosphides are believed to have an autonomous, gas-phase existence. The character of the bonding molecular orbitals has been analyzed.