in the present work, the regioselectivity for a series of diels–alder reactions (4 reactions) has beenstudied using hardness, electrophilicity and polarizability of products.furthermore,thermodynamicand kinetic calculations have been done. in all results predicted pararegioisomer is more favorableregioisomerinthese investigated reactions.all calculations have been done at the dft-b3lyp/6-31g(d)...

Projection-based embedding provides a simple and numerically robust framework for multiscale wavefunction-in-density-functional-theory (WF-in-DFT) calculations. The approach works well when the approximate DFT is sufficiently accurate to describe the energetics of the low-level subsystem and the coupling between subsystems. It is also necessary that the low-level DFT produces a qualitatively re...

in this paper, the structure of a new 16-membered macrocyclic schiff base compound n,n′-(3,3′-dimethoxy-2,2′-(propane-1,3-diyldioxy)dibenzylidene)propane-1,3-diamine, c22h26n2o4 (1), derived from 1,3-propanediamine and 3,3′-dimethoxy-2,2′-(propane-1,3-diyldioxy)dibenzaldehyde has been studied by single crystal x-ray diffraction, dft calculations at b3lyp/6-31g** and ft-ir spectroscopy. the titl...

The importance of including spin-orbit interactions for the correct description of structures and vibrational frequencies of haloiodomethanes is demonstrated by density functional theory calculations with spin-orbit relativistic effective core potentials (SO-DFT). The vibrational frequencies and the molecular geometries obtained by SO-DFT calculations do not match with the experimental results ...

The results of density-functional theory (DFT) calculations of the energy barriers for three lowbarrier relaxation processes in Ag/Ag(100) growth edge-zipping, atom-attraction and downward funneling (DF) are presented and compared with embedded atom method (EAM) calculations. In general, we find good agreement between the DFT values for these processes and the values assumed in recent simulatio...

Periodic density functional theory (DFT) calculations have recently emerged as a popular tool for assigning solid-state nuclear magnetic resonance (NMR) spectra. However, in order for the calculations to yield accurate results, accurate structural models are also required. In many cases the structural model (often derived from crystallographic diffraction) must be optimised (i.e., to an energy ...

the ir and nmr spectra were coupled with quantum chemical calculations in dft approach usingthe hybrid b3lyp exchange-correlation functional to confirm the structure of 2-methoxycarbonyl-7-methyl-1,3-thiazino[3,2-b][1,2,4]triazine-4,8-dione 2d.