Ion beam crystallography of surfaces and interfaces

We develop a nonempirical atoms-in-molecules (AIM) method for computing net atomic charges that simultaneously reproduce chemical states of atoms in a material and the electrostatic potential V(r) outside its electron distribution. This method gives accurate results for a variety of periodic and nonperiodic materials including molecular systems, solid surfaces, porous solids, and nonporous solids. This method, called DDEC/c3, improves upon our previously published DDEC/c2 method (Manz, T. A.; Sholl, D. S. J. Chem. Theory Comput. 2010, 6, 2455–2468) by accurately treating nonporous solids with short bond lengths. Starting with the theory all AIM charge partitioning functionals with spherically symmetric atomic weights must satisfy, the form of the DDEC/c3 functional is derived from first principles. The method is designed to converge robustly by avoiding conditions that lead to nearly flat optimization landscapes. In addition to net atomic charges, the method can also compute atomic multipoles and atomic s...

Improved Atoms-in-Molecule Charge Partitioning Functional for Simultaneously Reproducing the Electrostatic Potential and Chemical States in Periodic and Nonperiodic Materials.

Electronic properties on silicon-transition metal interface compounds

Epitaxial CoSi2 and NiSi2 thin films

Presentation d'une etude theorique et experimentale des proprietes electroniques de Ca 2 Si, CaSi et CaSi 2 . L'etude theorique est realisee par un calcul auto-coherent des etats electroniques. L'analyse experimentale est fondee sur des mesures de photoemission de radiation synchrotron. Mise en evidence du caractere covalent de la liaison Ca-Si, dont la force d'interaction croit avec la concentration en silicium. Dans CaSi 2 , on attribue a cette liaison un caractere ionique partiel

L. W. Chiao

Papers

Electronic structure and properties of Ni-Si(001) and Ni-Si(111) reactive interfaces

Electronic structure of vanadium silicides

Electronic structure and properties of silicon-transition metal interfaces