The interquark potential in charmonium states is calculated in both the zero and nonzero temperature phases from a first-principles lattice QCD calculation. Simulations with two dynamical quark flavors are used with temperatures T in the range 0.4Tc ≲ T ≲ 1.7Tc, where Tc is the deconfining temperature. The correlators of point-split operators are analyzed to gain spatial information about the c...

An ab initio approach to the calculation of excitonic effects in the optical absorption spectra of semiconductors and insulators is formulated. It starts from a quasiparticle band structure calculation and is based on the relevant Bethe-Salpeter equation. An application to bulk silicon shows a substantial improvement with respect to previous calculations in the description of the experimental s...

nowadays nmr spectroscopy becomes a powerful tool in chemistry because of the nmr chemical shifts. hartree–fock theory and the gauge-including atomic orbital (giao) methods are used in the calculation of 29si nmr chemical shifts of various silicate species in the silicate solution as initial components for zeolite synthesis both in gas and solution phase. calculations have been performed at geo...

The ab initio calculation of the ballistic current using full electronic structure and phonon dispersion shows that much larger responses can exist away from band-edge, provides a qualitatively different understanding for real materials.

SUPSIM is a web application, based on the Java Servlet technologies, to compute ab-initio potential energy surfaces of molecular systems for subsequent dynamical properties calculation. We describe the architecture of SUPSIM, its current implementation, and its possible future developments to tackle chemical systems of increasing complexity.

An algorithm for calculating the scattering factors of atomic fragments in molecules as defined by the Stockholder recipe is presented. This method allows the calculation, from ab initio molecular wave functions, of structure factors including individual anisotropic atomic temperature factors. These structure factors agree with the model used in most leastsquares multipole-refinement procedures...