Jahn-Teller distortions and the supershell effect in metal nanowires.

A Computational Study to Find the Vibrational Modes Connected with Specific Molecular Structures of Calculated Compound

The purpose of this research is to provide a deeper understanding of the planar high- symmetry configuration instability. In the ideal case, the distortion corresponds to the movements of nuclei along normal modes that belong to non-totally symmetric irreps of the high symmertry (HS) point group of molecule. The analysis of the structural distortion from the HS nuclear arrangements of the JT ac...

Effect of disorder in an orbitally ordered Jahn-Teller insulator

We study a two-dimensional, two-band double-exchange model for eg electrons coupled to Jahn-Teller distortions in the presence of quenched disorder using a recently developed Monte Carlo technique. In the absence of disorder the half-filled system at low temperatures is an orbitally ordered ferromagnetic insulator with a staggered pattern of Jahn-Teller distortions. We examine the finite-temper...

Metal-Insulator Transition in Mn Perovskite Compounds

We discuss Mott insulating and metallic phases of a model with eg orbital degeneracy to understand physics of Mn perovskite compounds. Quantum Monte Carlo and Lanczos diagonalization results are discussed in this model. To reproduce experimental results on charge gap and Jahn-Teller distortions, we show that a synergy between the strong correlation effects and the Jahn-Teller coupling is import...

Conductance quantization in metals: the influence of subband formation on the relative stability of specific contact diameters

We consider a simple model of a metallic nanowire, consisting of a free electron gas confined within hard wall boundaries and connected to banks on either side. Similar models have been widely used to discuss conductance properties of nanowires and point contacts. Here we show that the same model has implications for the mechanical stability of the wire and its work function, and that it possib...

Evidence of dynamic Jahn-Teller distortions in two-dimensional crystalline molecular films