Modeling of the phase evolution in Mg1-xAlxB2 (0 < x < 0.5) and its experimental signatures.

Despite the chemical and structural simplicity of MgB(2), at 39 K this compound has the highest known superconducting transition temperature (T(c)) of any binary compound. Electron doping by substituting Al for Mg leads to decreasing T(c), and the observed concentration dependent rate of decrease has been proposed to arise from the nonideal character of MgB(2)-AlB(2) solid solutions, which derives from the existence of an ordered Mg(0.5)Al(0.

Covalency trends in group IV metallocene dichlorides. chlorine K-edge X-ray absorption spectroscopy and time dependent-density functional theory.

For 3-5d transition-metal ions, the (C5R5)2MCl2 (R = H, Me for M = Ti, Zr, Hf) bent metallocenes represent a series of compounds that have been central in the development of organometallic chemistry and homogeneous catalysis. Here, we evaluate how changes in the principal quantum number for the group IV (C5H5)2MCl2 (M = Ti, Zr, Hf; 1- 3, respectively) complexes affects the covalency of M-Cl bonds through application of Cl K-edge X-ray Absorption Spectroscopy (XAS). Spectra were recorded on solid samples dispersed as a thin film and encapsulated in polystyrene matrices to reliably minimize problems associated with X-ray self-absorption.