Molecular photoswitches that are capable of storing solar energy, so-called molecular solar thermal storage systems, are interesting candidates for future renewable energy applications. In this context, substituted norbornadiene-quadricyclane systems have received renewed interest due to recent advances in their synthesis. The optical, thermodynamic, and kinetic properties of these systems can ...

The performance of 23 density functionals, including one LDA, four GGAs, three meta-GGAs, three hybrid GGAs, eight hybrid meta-GGAs, and ten double-hybrid functionals, was investigated for the computation of activation energies of various covalent main-group single bonds by four catalysts: Pd, PdCl(-), PdCl2, and Ni (all in the singlet state). A reactant complex, the barrier, and reaction energ...

We have quantum chemically investigated how methyl substituents affect the stability of alkyl radicals Me m H 3-m C • and corresponding C–X bonds (X = H, CH 3 , OH; 0 - 3) using density functional theory at M06-2X/TZ2P. The state-of-the-art in physical organic chemistry is that are stabilized upon an increase their degree substitution from < primary secondary tertiary, this underlying cause for...

In the current report, interaction of Al-doped carbon nanotubes (CNT) with carbazochrome, an anti-hemorrhagic or hemostatic agent, was investigated M06-2X functional and 6-31G* basis set. The global index including frontier molecular orbital energies, hardness, softness, chemical Gibbs energies some parameters NLO properties Carbazochrome, Al doped CNT complexes formed between their were calcul...

Adiabatic time-dependent density functional theory is a powerful method for calculating electronic excitation energies of complex systems, but the quality of the results depends on the choice of approximate density functional. In this article we test two promising new density functionals, M11 and M11-L, against databases of 214 diverse electronic excitation energies, and we compare the results ...

The geometries and binding energies of a recent buckyball tweezers (C(60)H(28)) and its supramolecular complexes are investigated using recently developed density functionals (M06-L and M06-2X) that include an accurate treatment of medium-range correlation energy. The pincer part of the tweezers, corannulene, has a strong attractive interaction with C(60). However, due to the entropy penalty, t...

Analytic first derivative expression of opposite-spin (OS) ansatz adapted quartic scaling doubly hybrid XYGJ-OS functional is derived and implemented into Q-Chem. The resulting algorithm scales quartically with system size as in OS-MP2 gradient, by utilizing the combination of Laplace transformation and density fitting technique. The performance of XYGJ-OS geometry optimization is assessed by c...

Product formation in the reaction of perfluorinated methyl vinyl ether, CF3OCF=CF2, with OH radicals is studied theoretically using the M06-2X/aug-cc-pVTZ and CCSD(T) levels of theory. The stable end-products in an oxidative atmosphere are predicted to be perfluorinated methyl formate, CF3OCFO, and fluorinated glycolaldehyde, CFOCF2OH, both with CF2O as coproduct. The prediction of glycolaldehy...

A detailed analysis of the selected DFT functionals for the calculations of interaction-induced dipole moment, polarizability and first-order hyperpolarizability has been carried out. The hydrogen-bonded model chains consisting of HF, H(2)CO and H(3)N molecules have been chosen as a case study. The calculations of the components of the static electric properties using the diffuse Dunning's basi...