We review the first successes and failures of a "new wave" of quantum chemistry-based approaches to the treatment of protein/ligand interactions. These approaches share the use of "enhanced", dispersion (D), and/or hydrogen-bond (H) corrected density functional theory (DFT) or semi-empirical quantum mechanical (SQM) methods, in combination with ensemble weighting techniques of some form to capt...

In this paper, quantum chemical parameters at density functional theory (DFT) B3LYP/6-31G** (d,p) level of theory were calculated for three organic corrosion inhibitors [N-benzoyl-N-(p-aminophenyl) thiourea, N-benzoyl-N-(thiazole) thiourea and N-acetyl-N-(dibenzyl) thiourea. The calculated molecular descriptors such as the HOMO, LUMO, dipole moment, chemical potential (μ), chemical hardness (ղ)...

Theoretical study of the electronic structure, NonLinear Optical (NLO) properties, and natural bonding orbital (NBO) analysis of 18-crown-6were investigated using Density Functional Theory (DFT) calculations at the B3LYP/6-311G (d,p) level of theory. The optimized structure is a nonlinear compound indicated from the dihedral angles.  Natural bonding orbital analys...

Standard density functional approximations often give questionable results for oddelectron radical complexes, with the error typically attributed to self-interaction. In density corrected density functional theory (DC-DFT), certain classes of density functional theory calculations are significantly improved by using densities more accurate than the self-consistent densities. We discuss how to i...

A metastable state, characterized by a low degree of mass localization, is identified using density-functional theory (DFT). This free energy minimum, located through the proper evaluation of competing terms in the free energy functional, is independent of the specific form of the DFT used. Computer simulation results on particle motion indicate that this heterogeneous state corresponds to the ...

We develop a classical density functional theory (DFT) for two-site associating fluids in spatially homogeneous external fields which exhibit orientational inhomogeneities. The Helmholtz free-energy functional is obtained using Wertheim's thermodynamic perturbation theory and the orientational distribution function is obtained using DFT in the canonical ensemble. It is shown that an orientating...

Nuclear density functional theory (DFT) is the only microscopic, global approach to the structure of atomic nuclei. It is used in numerous applications, from determining the limits of stability to gaining a deep understanding of the formation of elements in the universe or the mechanisms that power stars and reactors. The predictive power of the theory depends on the amount of physics embedded ...

Density-functional theory (DFT) for electrons at finite temperature is increasingly important in condensed matter and chemistry. The exact conditions that have proven crucial in constraining and constructing accurate approximations for ground-state DFT are generalized to finite temperature, including the adiabatic connection formula. We discuss consequences for functional construction.

Partition theory (PT) is a formally exact methodology for calculating the density of any molecule or solid via separate calculations on individual fragments. Just as Kohn-Sham density functional theory (DFT) introduces noninteracting fermions in an effective potential that is defined to yield the exact density of the interacting problem, in PT a global effective potential is found that ensures ...

We present the extension of Frozen Density Embedding (FDE) formulation of subsystem Density Functional Theory (DFT) to real-time Time Dependent Density Functional Theory (rt-TDDFT). FDE is a DFT-in-DFT embedding method that allows to partition a larger Kohn-Sham system into a set of smaller, coupled Kohn-Sham systems. Additional to the computational advantage, FDE provides physical insight into...