Rates and locations of C−C cleavage during the hydrogenolysis of alkyl-cyclohexanes determine the isomeric products of ring opening and the yield losses from dealkylation. Kinetically relevant transition states for C−C rupture form by sequential quasi-equilibrated dehydrogenation steps that break C−H bonds, form C−metal bonds, and desorb chemisorbed H atoms (H*) from H*-covered surfaces. Activa...

Using the first-principles plane-wave pseudopotential method within density functional theory, we have systematically investigated structural, electronic, and mechanical properties of M2Y6X6, Y6X6 X=Se,Te,S; Y =Mo,Cr,W; and M =Li,Na nanowires and bulk phase of M2Y6X6. We found that not only Mo6X6, but also transition metal and chalcogen atoms lying in the same columns of Mo and Se can form stab...

The apex atom plays a key role in STM tunneling, in particular if subtle effects like atomic and chemical resolution on metal alloys are considered. In order to provide comprehensive data on the electronic structure of realistic tips we have calculated tungsten (100) films with single apex atoms by first principles molecular dynamics and full potential methods. Molecular dynamics using ultrasof...

We consider the stimulated Raman transition between two long-lived states via multiple intermediate states, such as between hyperfine ground states in the alkali-metal atoms. We present a concise treatment of the general, multilevel, off-resonant case, and we show how the lightshift emerges naturally in this approach. We illustrate our results by application to alkali-metal atoms and we make sp...

We propose a novel representation of materials named an 'orbital-field matrix (OFM)', which is based on the distribution of valence shell electrons. We demonstrate that this new representation can be highly useful in mining material data. Experimental investigation shows that the formation energies of crystalline materials, atomization energies of molecular materials, and local magnetic moments...

Transition metal complexes containing Schiff base ligands are of interest to model the active sites of biologically important molecules. In particular, Schiff base derivatives of hydrazones exhibit various bioactivities and play vital role in certain physiological functions as well. Hydrazones and their metal complexes exhibit wide range of biological and pharmaceutical activities that includes...

The magic oxide clusters M 9O6 (M5Fe, Co, Ni) are found by using reactive laser vaporized cluster source. From the first-principles calculations, the possible equilibrium geometries for these three oxide clusters are determined to be a C2v symmetry, where the skeleton composed of 9 metal atoms also has C2v symmetry, different from the equilibrium structures of pure transition metal cluster M 9 ...