Spurious Oscillations Caused by Density Functional Approximations: Who is to Blame? Exchange or Correlation? DOI Creative Commons
Sebastian P. Sitkiewicz, Rubén R. Ferradás, Eloy Ramos‐Cordoba

et al.

Journal of Chemical Theory and Computation, Journal Year: 2024, Volume and Issue: 20(8), P. 3144 - 3153

Published: April 3, 2024

We analyze the varying susceptibilities of different density functional approximations (DFAs) to present spurious oscillations on profiles several vibrational properties. Among other problems, these cause significant errors in harmonic and anharmonic IR Raman frequencies intensities. This work hinges a judicious strategy dissect exchange correlation components DFAs pinpoint origins oscillations. identify derivatives all energy with respect nuclear displacements, including those terms that do not involve numerical integrations. These

Language: Английский

Best‐Practice DFT Protocols for Basic Molecular Computational Chemistry** DOI
Markus Bursch, Jan‐Michael Mewes, Andreas Hansen

et al.

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(42)

Published: Sept. 14, 2022

Nowadays, many chemical investigations are supported by routine calculations of molecular structures, reaction energies, barrier heights, and spectroscopic properties. The lion's share these quantum-chemical applies density functional theory (DFT) evaluated in atomic-orbital basis sets. This work provides best-practice guidance on the numerous methodological technical aspects DFT three parts: Firstly, we set stage introduce a step-by-step decision tree to choose computational protocol that models experiment as closely possible. Secondly, present recommendation matrix guide choice depending task at hand. A particular focus is achieving an optimal balance between accuracy, robustness, efficiency through multi-level approaches. Finally, discuss selected representative examples illustrate recommended protocols effect choices.

Language: Английский

Citations

474
TURBOMOLE: Today and Tomorrow DOI Creative Commons
Yannick J. Franzke, Christof Holzer, Josefine H. Andersen

et al.

Journal of Chemical Theory and Computation, Journal Year: 2023, Volume and Issue: 19(20), P. 6859 - 6890

Published: June 29, 2023

TURBOMOLE is a highly optimized software suite for large-scale quantum-chemical and materials science simulations of molecules, clusters, extended systems, periodic solids. uses Gaussian basis sets has been designed with robust fast applications in mind, ranging from homogeneous heterogeneous catalysis to inorganic organic chemistry various types spectroscopy, light-matter interactions, biochemistry. This Perspective briefly surveys TURBOMOLE's functionality highlights recent developments that have taken place between 2020 2023, comprising new electronic structure methods molecules solids, previously unavailable molecular properties, embedding, dynamics approaches. Select features under development are reviewed illustrate the continuous growth program suite, including nuclear orbital methods, Hartree-Fock-based adiabatic connection models, simplified time-dependent density functional theory, relativistic effects magnetic multiscale modeling optical properties.

Language: Английский

Citations

125
Best‐Practice DFT Protocols for Basic Molecular Computational Chemistry** DOI Creative Commons
Markus Bursch, Jan‐Michael Mewes, Andreas Hansen

et al.

Angewandte Chemie, Journal Year: 2022, Volume and Issue: 134(42)

Published: Sept. 14, 2022

Abstract Nowadays, many chemical investigations are supported by routine calculations of molecular structures, reaction energies, barrier heights, and spectroscopic properties. The lion's share these quantum‐chemical applies density functional theory (DFT) evaluated in atomic‐orbital basis sets. This work provides best‐practice guidance on the numerous methodological technical aspects DFT three parts: Firstly, we set stage introduce a step‐by‐step decision tree to choose computational protocol that models experiment as closely possible. Secondly, present recommendation matrix guide choice depending task at hand. A particular focus is achieving an optimal balance between accuracy, robustness, efficiency through multi‐level approaches. Finally, discuss selected representative examples illustrate recommended protocols effect choices.

Language: Английский

Citations

95
A direct observation of up-converted room-temperature phosphorescence in an anti-Kasha dopant-matrix system DOI Creative Commons
Jiuyang Li, Xun Li, Guangming Wang

et al.

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: April 8, 2023

It is common sense that emission maxima of phosphorescence spectra (λP) are longer than those fluorescence (λF). Here we report a serendipitous finding up-converted room-temperature (RTP) with λP < λF and lifetime > 0.1 s upon doping benzophenone-containing difluoroboron β-diketonate (BPBF2) into phenyl benzoate matrices. The RTP originated from BPBF2's Tn (n ≥ 2) states which show typical 3n-π* characters benzophenone moieties. Detailed studies reveal that, intersystem crossing S1 charge transfer characters, the resultant T1 build T1-to-Tn equilibrium. Because their possess large rates can strongly compete RTP(T1) to directly emit RTP(Tn) violates Kasha's rule. direct observation provides deep understanding triplet excited state dynamics opens an intriguing pathway devise visible-light-excitable deep-blue afterglow emitters, as well stimuli-responsive materials.

Language: Английский

Citations

59
Application of the noncollinear Scalmani–Frisch formalism to current density functional theory DOI Creative Commons
Yannick J. Franzke, Ansgar Pausch, Christof Holzer

et al.

The Journal of Chemical Physics, Journal Year: 2025, Volume and Issue: 162(8)

Published: Feb. 25, 2025

We generalize the noncollinear formalism proposed by Scalmani and Frisch [J. Chem. Theory Comput. 8, 2193 (2012)] to include particle spin current densities for meta-generalized gradient approximations local hybrid functionals. This allows us fully impact of spin–orbit coupling in relativistic calculations applications finite magnetic fields. For latter, we use London atomic orbitals ensure gauge origin invariance. It is shown that this superior more common canonical approach calculations, as it naturally includes all three closed-shell limit avoids projection onto magnetization vector. important easily restore rotational invariance limit. In addition, Scalmani–Frisch can be made numerically stable may lead a nonvanishing torque. However, both formalisms are rotationally invariant open-shell systems

Language: Английский

Citations

2
On the origin of the inverted singlet–triplet gap of the 5th generation light-emitting molecules DOI Creative Commons
Lucie Tučková, Michal Straka, Rashid R. Valiev

et al.

Physical Chemistry Chemical Physics, Journal Year: 2022, Volume and Issue: 24(31), P. 18713 - 18721

Published: Jan. 1, 2022

Excitation energies of the lowest singlet and triplet state molecules whose first excited lies energetically below have been studied computationally at (time-dependent) density functional theory, coupled-cluster, second-order multiconfiguration perturbation theory levels. The calculations ab initio levels show that singlet-triplet gap is inverted as compared to one expected from Hund's rule, whereas all functionals yield state. Double excitations responsible for identified. Employing spin-flip ΔSCF methods, inversion was obtained level some molecules.

Language: Английский

Citations

45
Impact of the current density on paramagnetic NMR properties DOI Creative Commons
Yannick J. Franzke, Christof Holzer

The Journal of Chemical Physics, Journal Year: 2022, Volume and Issue: 157(3)

Published: June 27, 2022

Meta-generalized gradient approximations (meta-GGAs) and local hybrid functionals generally depend on the kinetic energy density τ. For magnetic properties, this necessitates generalizations to ensure gauge invariance. In most implementations, τ is generalized by incorporating external field. However, introduces artifacts in response of matrix does not satisfy iso-orbital constraint. Here, we extend previous approaches based current paramagnetic nuclear resonance (NMR) shieldings electron (EPR) g-tensors. The impact assessed for main-group compounds transition-metal complexes considering 25 functional approximations. It shown that leads substantial improvements-especially popular Minnesota strongly constrained appropriately normed (SCAN) families. Thus, recommend use NMR EPR calculations with meta-GGAs.

Language: Английский

Citations

39
Density-functional theory for electronic excited states DOI
John M. Herbert

Elsevier eBooks, Journal Year: 2023, Volume and Issue: unknown, P. 69 - 118

Published: Jan. 1, 2023

Language: Английский

Citations

27
Comment on “Benchmarking Basis Sets for Density Functional Theory Thermochemistry Calculations: Why Unpolarized Basis Sets and the Polarized 6-311G Family Should Be Avoided” DOI Creative Commons
Montgomery Gray, Paige E. Bowling, John M. Herbert

et al.

The Journal of Physical Chemistry A, Journal Year: 2024, Volume and Issue: 128(36), P. 7739 - 7745

Published: Aug. 27, 2024

Language: Английский

Citations

10
In Defense of (Certain) Pople-Type Basis Sets DOI Creative Commons
Montgomery Gray, Paige E. Bowling, John M. Herbert

et al.

Published: Jan. 22, 2024

A recent study suggests that Gaussian basis sets in the 6-311G family are inappropriate for thermochemical calculations based on density functional theory, emphasizing need polarization functions but omitting tests of Pople containing a full complement thereof. Here, we point out certain category yield error statistics with respect to benchmark comparable def2-TZVP, at about half cost. More elaborate can rival accuracy def2-QZVPD 5-10% We also clarify role integral thresholds achieving robust convergence presence diffuse functions.

Language: Английский

Citations

9