Benchmarking quantum chemistry methods for spin-state energetics of iron complexes against quantitative experimental data

2019 ◽  
Vol 21 (9) ◽  
pp. 4854-4870 ◽  
Author(s):  
Mariusz Radoń
Keyword(s):  
Experimental Data ◽  
Wave Function ◽  
Quantum Chemistry ◽  
Spin State ◽  
Iron Complexes ◽  
P Wave ◽  
Dft Methods ◽  
Benchmark Data

Wave function and DFT methods tested against quantitative, experimentally-derived benchmark data of relative spin-state energetics for iron complexes.

Spin-state energetics of metallocenes: How do best wave function and density functional theory results compare with the experimental data?

2021 ◽  
Vol 23 (1) ◽  
pp. 151-172
Author(s):  
Gabriela Drabik ◽  
Janusz Szklarzewicz ◽  
Mariusz Radoń
Keyword(s):  
Experimental Data ◽  
Density Functional Theory ◽  
Wave Function ◽  
Spin State ◽  
Quantum Chemical ◽  
Density Functional ◽  
Chemical Methods ◽  
Functional Theory ◽  
Quantum Chemical Methods

Benchmarking quantum-chemical methods against experiment-derived spin-state energetics of metallocenes.

scholarly journals Soft experimental constraints for soft interactions: a spectroscopic benchmark data set for weak and strong hydrogen bonds

2019 ◽  
Vol 21 (35) ◽  
pp. 18799-18810 ◽  
Author(s):  
Sönke Oswald ◽  
Martin A. Suhm
Keyword(s):  
Experimental Data ◽  
Hydrogen Bonds ◽  
Quantum Chemistry ◽  
Harmonic Approximation ◽  
Data Set ◽  
Benchmark Data ◽  
Small Set ◽  
Soft Interactions ◽  
Bonded Complexes ◽  
Hydrogen Bonded

Experimental data for hydrogen-bonded complexes between a small set of test molecules are converted into a benchmark set for quantum chemistry predictions in the convenient harmonic approximation.

Study of potential curves by UHF type methods. CH4 molecule and its dissociation products

1986 ◽  
Vol 51 (4) ◽  
pp. 731-737
Author(s):  
Viliam Klimo ◽  
Jozef Tiňo
Keyword(s):  
Experimental Data ◽  
Quantum Chemistry ◽  
High Energy ◽  
Basis Set ◽  
Electronic Correlation ◽  
Exact Methods ◽  
Energy Parameters ◽  
Bond Functions ◽  
The Individual ◽  
Potential Curves

Geometry and energy parameters of the individual dissociation intermediate steps of CH4 molecule, parameters of the barrier to linearity and singlet-triplet separation of the CH2 molecule have been calculated by means of the UMP method in the minimum basis set augmented with the bond functions. The results agree well with experimental data except for the geometry of CH2(1A1) and relatively high energy values of CH(2II) and CH2(1A1) where the existence of two UHF solutions indicates a necessity of description of the electronic correlation by more exact methods of quantum chemistry.

Wave Function–Based Quantum Chemistry

2003 ◽  
Author(s):  
Poul J√òRgensen ◽  
Jeppe Olsen ◽  
Trygve Helgaker ◽  
Wim Klopper
Keyword(s):  
Wave Function ◽  
Quantum Chemistry

scholarly journals Spin-Spin Coupling Constants 1J(15N,11B) in Boron-Nitrogen Compounds. Experimental Data and DFT Calculations

2007 ◽  
Vol 62 (2) ◽  
pp. 220-224 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Oleg L. Tok
Keyword(s):  
Experimental Data ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Positive Sign ◽  
Nitrogen Compounds ◽  
Dft Methods ◽  
Spin Coupling Constants ◽  
Fermi Contact ◽  
Spin Spin Coupling ◽  
Boron Nitrogen

Boron-nitrogen compounds were studied with respect to indirect nuclear 15N-11B spin-spin coupling (1J(15N,11B)). Some new experimental data were determined for aminoboranes and tetra-Npyrrolylborate, and a variety of compounds with B-N single, double and triple bonds were examined using DFT methods for the calculation of 1J(15N,11B) at the B3LYP/6-311+G(d,p) level of theory. The calculations predict magnitude and sign of 1J(15N,11B) reasonably well, and the Fermi contact term was found to be dominant. A positive sign of 1J(15N,11B) was calculated in the case of 1-azacloso- dodecaborane(12), in contrast to all other compounds studied.

scholarly journals Mobility Enhancement in Square Quantum Wells: Symmetric Modulation of the Envelop Wave Function

2010 ◽  
Vol 20 (3) ◽  
pp. 193
Author(s):  
Doan Nhat Quang ◽  
Nguyen Huyen Tung ◽  
Nguyen Trung Hong ◽  
Tran Thi Hai
Keyword(s):  
Experimental Data ◽  
Wave Function ◽  
Low Temperature ◽  
Quantum Wells ◽  
Quantum Transport ◽  
Variational Approach ◽  
Theoretical Study ◽  
Recent Experimental Data ◽  
Carrier Distribution ◽  
Analytic Expressions

We present a theoretical study of the effects from symmetric modulation of the envelop wave function on quantum transport in square quantum wells (QWs). Within the variational approach we obtain analytic expressions for the carrier distribution and their scattering in symmetric two-side doped square QWs. Roughness-induced scattering are found significantly weaker than those in the asymmetric one-side doped counterpart. Thus, we propose symmetric modulation of the wave function as an efficient method for enhancement of the roughness-limited QW mobility. Our theory is able to well reproduce the recent experimental data about low-temperature transport of electrons and holes in two-side doped square QWs, e.g., the mobility dependence on the channel width, which have not been explained so far.

Density Functional Approaches to Relativistic Quantum Mechanics

2007 ◽  
Author(s):  
Kenneth G. Dyall ◽  
Knut Faegri
Keyword(s):  
Wave Function ◽  
Quantum Mechanics ◽  
Electron Density ◽  
Density Functional ◽  
Relativistic Quantum ◽  
Electron System ◽  
State Density ◽  
Dft Methods ◽  
Particle Wave Function ◽  
Spatial Coordinates

The wave function is an elusive and somewhat mysterious object. Nobody has ever observed the wave function directly: rather, its existence is inferred from the various experiments whose outcome is most rationally explained using a wave function interpretation of quantum mechanics. Further, the N-particle wave function is a rather complicated construction, depending on 3N spatial coordinates as well as N spin coordinates, correlated in a manner that almost defies description. By contrast, the electron density of an N-electron system is a much simpler quantity, described by three spatial coordinates and even accessible to experiment. In terms of the wave function, the electron density is expressed as . . . ρ(r) = N ∫ Ψ* (r1,r2,...,rN)Ψ (r1,r2,...,rN)dr2dr3 ...drN (14.1) . . . where the sum over spin coordinates is implicit. It might be much more convenient to have a theory based on the electron density rather than the wave function. The description would be much simpler, and with a greatly reduced (and constant) number of variables, the calculation of the electron density would hopefully be faster and less demanding. We also note that given the correct ground state density, we should be able to calculate any observable quantity of a stationary system. The answer to these hopes is density functional theory, or DFT. Over the past decade, DFT has become one of the most widely used tools of the computational chemist, and in particular for systems of some size. This success has come despite complaints about arbitrary parametrization of potentials, and laments about the absence of a universal principle (other than comparison with experiment) that can guide improvements in the way the variational principle has led the development of wave-function-based methods. We do not intend to pursue that particular discussion, but we note as a historical fact that many important early contributions to relativistic quantum chemistry were made using DFT-like methods. Furthermore, there is every reason to try to extend the success of nonrelativistic DFT methods to the relativistic domain. We suspect that their potential for conquering a sizable part of this field is at least as large as it has been in the nonrelativistic domain.

Bohr Hamiltonian with screened Kratzer potential for triaxial nuclei

2020 ◽  
Vol 29 (10) ◽  
pp. 2050082
Author(s):  
Y. Omon ◽  
J. M. Ema’a Ema’a ◽  
P. Ele Abiama ◽  
G. H. Ben-Bolie ◽  
P. Owono Ateba
Keyword(s):  
Experimental Data ◽  
Wave Function ◽  
Energy Spectrum ◽  
Experiment Data ◽  
Uvarov Method ◽  
Good Agreement

In this paper, Bohr Hamiltonian is used to describe the behaviors of triaxial nuclei with screened Kratzer potential. The Nikivorov–Uvarov method is used to derive the energy spectrum and corresponding wave function. The electric quadruple transition ratios and energy spectrum of the [Formula: see text]Xe, [Formula: see text]Xe, [Formula: see text]Xe, [Formula: see text]Xe, [Formula: see text]Xe, [Formula: see text]Pt, [Formula: see text]Pt and [Formula: see text]Pt are calculated and compared with the experimental data. The results are in good agreement with experiment data.

Determination of hyperon properties through the variational method considering the hyperfine interaction

2019 ◽  
Vol 28 (10) ◽  
pp. 1950087 ◽  
Author(s):  
S. M. Moosavi Nejad ◽  
A. Armat
Keyword(s):  
Experimental Data ◽  
Wave Function ◽  
Ground State ◽  
Radiative Decay ◽  
Magnetic Moments ◽  
Wave Functions ◽  
Decay Widths ◽  
Free Parameters ◽  
Theoretical Results

Performing a fit procedure on the hyperon masses, we first determine the free parameters in the Cornell-like hypercentral potential between the constituent quarks of hyperons in their ground state. To this end, using the variational principle, we apply the hyperspherical Hamiltonian including the Cornell-like hypercentral potential and the perturbation potentials due to the spin–spin, spin–isospin and isospin–isospin interactions between constituent quarks. In the following, we compute the hyperon magnetic moments as well as radiative decay widths of spin-3/2 hyperons using the spin-flavor wave function of hyperons. Our analysis shows acceptable consistencies between theoretical results and available experimental data. This leads to reliable wave functions for hyperons at their ground state.

scholarly journals Importance of the Basis Set for the Spin-State Energetics of Iron Complexes

2008 ◽  
Vol 112 (28) ◽  
pp. 6384-6391 ◽  
Author(s):  
Mireia Güell ◽  
Josep M. Luis ◽  
Miquel Solà ◽  
Marcel Swart
Keyword(s):  
Spin State ◽  
Iron Complexes ◽  
Basis Set
Sign in / Sign up

Export Citation Format

Share Document