Advances in molecular quantum chemistry contained in the Q-Chem 4 program package

Y Shao, Z Gan, E Epifanovsky, ATB Gilbert… - Molecular …, 2015 - Taylor & Francis
A summary of the technical advances that are incorporated in the fourth major release of the
q-Chem quantum chemistry program is provided, covering approximately the last seven …

At what chain length do unbranched alkanes prefer folded conformations?

JN Byrd, RJ Bartlett… - The Journal of Physical …, 2014 - ACS Publications
Short unbranched alkanes are known to prefer linear conformations, whereas long
unbranched alkanes are folded. It is not known with certainty at what chain length the linear …

The performance of density functionals for sulfate–water clusters

N Mardirossian, DS Lambrecht… - Journal of chemical …, 2013 - ACS Publications
The performance of 24 density functionals, Hartree–Fock, and MP2 is assessed with respect
to the CCSD (T)/CBS* energetics of 49 sulfate–water clusters with three to six water …

Dual basis set approach for density functional and wave function embedding schemes

B Hegely, PR Nagy, M Kallay - Journal of chemical theory and …, 2018 - ACS Publications
A dual basis (DB) approach is proposed which is suitable for the reduction of the
computational expenses of the Hartree–Fock, Kohn–Sham, and wave function-based …

Computation of hydration free energies using the multiple environment single system quantum mechanical/molecular mechanical method

G König, Y Mei, FC Pickard IV… - Journal of chemical …, 2016 - ACS Publications
A recently developed MESS-E-QM/MM method (multiple-environment single-system
quantum mechanical molecular/mechanical calculations with a Roothaan-step …

Adaptive-partitioning multilayer dynamics simulations: 1. On-the-fly switch between two quantum levels of theory

J Mato, AW Duster, EB Guidez… - Journal of chemical theory …, 2021 - ACS Publications
We propose to generalize the previously developed two-layer permuted adaptive-
partitioning quantum-mechanics/molecular-mechanics (QM/MM), which reclassifies atoms …

Use of an auxiliary basis set to describe the polarization in the fragment molecular orbital method

DG Fedorov, K Kitaura - Chemical Physics Letters, 2014 - Elsevier
We developed a dual basis approach within the fragment molecular orbital formalism
enabling efficient and accurate use of large basis sets. The method was tested on water …

Non-covalent interactions with dual-basis methods: Pairings for augmented basis sets

RP Steele, RA DiStasio Jr… - Journal of Chemical …, 2009 - ACS Publications
Basis set pairings for dual-basis calculations are presented for the aug-cc-pVXZ (X= D, T, Q)
series of basis sets. Fidelity with single-basis results is assessed at the second-order …

[HTML][HTML] Approaching the basis set limit for DFT calculations using an environment-adapted minimal basis with perturbation theory: Formulation, proof of concept, and …

Y Mao, PR Horn, N Mardirossian… - The Journal of …, 2016 - pubs.aip.org
Recently developed density functionals have good accuracy for both thermochemistry (TC)
and non-covalent interactions (NC) if very large atomic orbital basis sets are used. To …

Analytic gradients for local density fitting Hartree–Fock and Kohn–Sham methods

J Csóka, M Kállay - The Journal of Chemical Physics, 2023 - pubs.aip.org
We present analytic gradients for local density fitting Hartree–Fock (HF) and hybrid Kohn–
Sham (KS) density functional methods. Due to the non-variational nature of the local fitting …