Molecular fractionation with conjugate caps (MFCC) method is introduced for the efficient estimation of quantum mechanical (QM) interaction energies between nanomaterial (carbon nanotube, fullerene, and graphene surface) and ligand (charged and neutral). In the calculations, nanomaterials are partitioned into small fragments and conjugated caps that are properly capped, and the interaction ener...

Coinage metal cyanides (MCN) form photoluminescent 1D coordination polymers. The decoration of these chains with amine and phosphine ligands shifts the wavelength for photoluminescence into the visible region. Density-functional theory (DFT) and time-dependent DFT (TD-DFT) calculations of zigzag and helical models of decorated chains are used to show that the transitions that contribute to the ...

Adequate polarization functions reduce the error of density functional theory (DFT) for the heat of reaction for CF(4) + SiCl(4) from ∼9-12 kcal mol(-1) to ∼2-4 kcal mol(-1), and using an improved density functional further reduces it to ∼1 kcal mol(-1). This reaction was previously identified as a stumbling block for DFT, but we show that the problem with the previous calculations was not DFT ...

Ab initio and density functional methods have been employed to study bridge bonding of aluminum compounds. Results for geometry optimizations and vibrational frequency calculations are found to be consistent with the recent literature. Heats of formation for the aluminum compounds dimethylaluminum hydride and trimethylaluminum are poorly described with density functional theory (DFT) methods in...

Over the last couple of years, it has been shown that Time Dependent Density Functional Theory (TD-DFT) is able to predict accurately and efficiently the polarizability of molecules, when using appropriate exchange-correlation potentials and (large) basis sets. In a previous paper, we compared the accuracy of the predicted mean polarizabilities of 15 organic molecules with experiment, and with ...

We outline the main ideas underlying the CONQUEST code for first-principles modelling of systems containing many thousands of atoms, focusing on the algorithms used to achieve linear-scaling of the cpu and memory requirements with number of atoms, and the strategies for implementing the algorithms so as to achieve good parallel scaling on parallel computers. We note that the code can be run at ...

one main group of organic chemistry is related to the aromatic compounds. in the present work, we replaced the ch group of benzene by silicon and nitrogen analogues. then, density functional theory (dft) calculations were carried out for six-membered heterocyclic si-n aromatic rings. full geometry optimizations were performed in gas-phase, and at b3lyp level using 6-311++g(d,p) and cbsb7 basis ...