There are two different pictures of molecular structure: the classical and the quantummechanical. The classical picture is naive-empirical and is the chemical one; it is connected with classical structural formulae, ball-and-stick models, the phenomenological Lewis concept and the Gillespy rules for prediction of molecular geometry. This picture now endures as the heuristic instrument for the p...

Finding transition paths for chemical reactions can be computationally costly owing to the level of quantum-chemical theory needed for accuracy. Here, we show that a multilevel preconditioning scheme that was recently introduced (Tempkin et al. J. Chem. Phys.2014, 140, 184114) can be used to accelerate quantum-chemical string calculations. We demonstrate the method by finding minimum-energy pat...

Different quantum chemical approaches to the ground state correlation energy per unit cell of infinite poly(para-phenylene) (PPP) chains are presented. PPP is an organic polymer with interesting optical properties, due to its conjugated, aromatic pi system. The inclusion of correlation effects is crucial for a sound quantum chemical description of such a system. The correlation calculations wer...

The vibrational spectra of UBz and ThBz have been measured in solid argon. Complementary quantum chemical calculations have allowed the assignments of the vibrational spectra. According to the calculations, AcBz are stable molecules, as well as other species like BzAcBz and BzAc2Bz. Experimentally, there is no evidence for the sandwich compounds BzAcBz and BzAc2Bz due to the limitations in the ...

Quantum chemical calculations on possible decomposition processes for ladderane lipids are described. Based on the results of these calculations, it is proposed that hydrogen atom abstraction next to the ladderane core can lead to opening of the cyclobutane rings comprising the ladderane substructure, and protonation leads directly to fragmentation. Potential biological implications of these pr...

in this study we investigate the effect of atoms such as b, n, ge and sn on the optical and the electrical properties of capped (5, 0) zigzag carbon nanotube, using dft calculation method. these elements were attached to the one end of the carbon nanotube. we considered four different structure designs as possible candidates for a p-n junction device. the electrical properties of these structur...