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## Interplay between test sets and statistical procedures in ranking DFT methods: The case of electron density studies

Mendeleev Communications. 2018. Vol. 28. No. 3. P. 225-235.

The task of choosing a reliable density functional (DFT) approximation remains one of the most puzzling ones in quantum chemical modeling and materials simulations. Since DFT functionals are in general not systematically improvable, benchmarking them on specifically designed test sets is the usual way for identifying a method best suited for a particular purpose. To get an answer from a bunch of numbers, statistical analysis should be applied. In this article the possibilities and pitfalls of statistical error analysis are discussed, taking as an example the ranking of approximate functionals by the accuracy of their self-consistent electron densities, which were recently shown to have worsened in the last decade.

Priority areas:
IT and mathematics

Language:
English

Medvedev M., Bushmarinov I., Sun J. et al., Science 2017 Vol. 355 No. 6320 P. 49-52

The theorems at the core of density functional theory (DFT) state that the energy of a many-electron system in its ground state is fully defined by its electron density distribution. This connection is made via the exact functional for the energy, which minimizes at the exact density. For years, DFT development focused on energies, implicitly ...

Added: October 12, 2019

Medvedev M., Zeifman A., Novikov F. et al., Journal of the american chemical society 2017 Vol. 139 No. 11 P. 3942-3945

The Diels–Alder reaction is a cornerstone of modern organic synthesis. Despite this, it remains essentially inaccessible to biosynthetic approaches. Only a few natural enzymes catalyze even a formal [4 + 2] cycloaddition, and it remains uncertain if any of them proceed via the Diels–Alder mechanism. In this study, we focus on the [4 + 2] ...

Added: October 12, 2019

Akchurin I., Yakhutina A., Bochkov A. et al., Journal of Molecular Structure 2018 Vol. 1160 P. 215-221

Novel push-pull fluorescent dyes – 7-(diethylamino)furo- and 7-(diethylamino)thieno[3,2-c]coumarins derivatives have been synthesized using formyl derivatives of furo- and thieno[3,2-c]coumarins as starting materials. Electron absorption and fluorescent spectra of the dyes have been recorded in different solvents. Effects of dyes structure and solvent on their spectral characteristics were analyzed. The fusion of five-membered heterocycle to coumarin ...

Added: October 12, 2019

Traven V., Pozharskaya N., Solovjova N. et al., Dyes and Pigments 2017 Vol. 136 P. 612-618

New aryl(hetaryl)pyrazolines fitted for fluorescence activation of Rhodamine laser dyes have been obtained via one-pot tandem Michael addition of two arylhydrazine molecules with 2-(4′-R-cinnamyliden)-2Н-furo[3,2-≿]coumarin-3-ones. These aryl(hetaryl)pyrazolines do not undergo tautomeric transformations both in organic solvents and in polymer films and behave themselves as effective acid photogenerators of Rhodamine dyes fluorescence activation. New aryl(hetaryl)pyrazolines can be ...

Added: October 12, 2019

Heindl C., Peresypkina E., Virovets A. et al., Angewandte Chemie - International Edition 2017 Vol. 56 No. 43 P. 13237-13243

Pentaphosphaferrocenes [CpRFe(η5-P5)] (1) and CuI halides are excellent building blocks for the formation of discrete supramolecules. Herein, we demonstrate the potential of Cu(CF3SO3) for the construction of the novel 2D polymer [{Cp*Fe(μ4,η5:1:1:1-P5)}{Cu(CF3SO3)}]n (2) and the unprecedented nanosphere (CH2Cl2)1.4@[{CpBnFe(η5-P5)}12{Cu(CF3SO3)}19.6] (3). The supramolecule 3 has a unique scaffold beyond the fullerene topology, with 20 copper atoms statistically ...

Added: October 12, 2019

Cruchter T., Medvedev M., Shen X. et al., ACS Catalysis 2017 Vol. 7 No. 8 P. 5151-5162

Herein, we report about the design, synthesis, and application of a nucleophilic octahedral chiral-only-at-metal iridium(III) complex. We demonstrate that the enantiopure form of this complex serves as an efficient catalyst for the asymmetric Steglich rearrangement of O-acylated azlactones (up to 96% ee and 99% yield) and the related asymmetric Black rearrangement of O-acylated benzofuranones (up to 94% ...

Added: October 12, 2019

Norman G., Saitov I., Stegailov V. et al., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2015 Vol. 91 No. 023105 P. 1-10

Reflectivity of shocked compressed xenon plasma is calculated within the framework of the density functional theory approach. Dependencies on the frequency of incident radiation and on the plasma density are analyzed. The Fresnel formula for the reflectivity is used. The longitudinal expression in the long-wavelength limit is applied for the calculation of the imaginary part ...

Added: March 15, 2017

Norman G., Saitov I., Доклады Российской академии наук. Физика, технические науки (ранее - Доклады Академии Наук. Физика) 2017 Т. 474 № 6 С. 687-691

The density functional theory is used to calculate the equation of state and the proton-proton pair correlation functions in the range of hydrogen temperatures and densities where the fluid-fluid-phase transition is expected. The metastable states are considered. The critical temperature has been estimated to be ~4000 K. We propose a two-step mechanism: the partial ionization ...

Added: December 2, 2017

Stegailov V., Zhilyaev P. A., Contributions to Plasma Physics 2015 Vol. 55 No. 2-3 P. 164-171

Non-equilibrium two-temperature warm dense metals consist of the ion subsystem that is subjected to structural transitions and involved in the mass transfer, and the electron subsystem that in various pulsed experiments absorbs energy and then evolves together with ions to equilibrium. Definition of pressure in such non-equilibrium systems causes certain controversy. In this work we ...

Added: March 15, 2017

Ivanov S., Dmitrienko A., Medvedev M. et al., Journal of Organometallic Chemistry 2019 Vol. 896 P. 168-182

7-Lithio-3-tert-butylpyrazolo[5,1-c][1,2,4]triazines have been generated for the first time using one-pot nucleophilic addition and metal-halogen exchange reactions in 7-bromopyrazolo[5,1-c][1,2,4]triazines. It was found that the stability of 7-lithio species depends highly on the substitution pattern at the C(4) ring position. The rate of the pyrazole ring opening reaction roughly followed the order of the electronegativity of substituents: ...

Added: October 12, 2019

Medvedev M., Salikov R., Trainov K. et al., Dyes and Pigments 2019 Vol. 161 P. 500-509

Two approaches for the synthesis of D-A chromophores containing arylhydrazonocyclopentadiene acceptor moieties were developed. The first approach includes the decarboxylative azo coupling reaction between penta(methoxycarbonyl)cyclopentadienyl potassium or sodium and aryldiazonium salts to give products containing four ester groups at the acceptor moiety. The second one includes the reaction of 1,3-dimethoxycarbonyl-4,5-diphenylcyclopentadienone with arylhydrazine hydrochlorides into arylhydrazonocyclopentadienes ...

Added: October 9, 2019

Omelchuk O., Malyshev V., Medvedev M. et al., Journal of Organic Chemistry 2021 Vol. 86 No. 12 P. 7975-7986

Oligomycin A is a potent antibiotic and antitumor agent. However, its applications are restricted by its high toxicity and low bioavailability. In this study, we obtained Oligomycin A Diels− Alder adducts with benzoquinone and N-benzylmaleimide and determined their absolute conﬁgurations by combining 1H and ROESY NMR data with molecular mechanics conformational analysis and quantum chemical ...

Added: September 6, 2021

Остроумова Г. М., Орехов Н. Д., Stegailov V., Diamond and Related Materials 2019 Vol. 94 P. 14-20

Formation of carbon nanoparticles is an important type of complex non-equilibrium processes that require precise atomistic theoretical understanding. In this work, we consider the process of ultrafast cooling of pure carbon gas that results in nucleation of an onion-like fullerene. The model is based on molecular dynamics simulation with the interaction between carbon atoms described ...

Added: February 22, 2019

Medvedev M., Kuznetsov N., Malishev V. et al., Mendeleev Communications 2019 Vol. 29 P. 190-193

Triallylborane-mediated thermal trans/cis-isomerization of α-allylated azaheterocycles is a unique stereoselective transformation providing straightforward access to important heterocycles. The main experimental features of this process, namely, thermodynamically controlled isomer ratio, 1,3-allylic strain as a driving force and regioselectivity are quantitatively described by quantum chemical calculations at B3LYP/6-31+G(d,p)/PCM(DMSO) level of theory. ...

Added: October 12, 2019

Isaev E., Lysakov S., Sukhov R. et al., Odessa Astronomical Publications 2013 No. 26/2 P. 309

Added: December 11, 2013

Zhukova E. I., Malova H. V., V. Yu. Popov et al., Cosmic Research 2017 Vol. 55 No. 6 P. 417-425

This work is devoted to studying the processes of the acceleration of plasma particles in thin current sheets that appear during magnetospheric substorms in the Earth’s magnetosphere tail. A numerical model of magnetic dipolarization accompanied by plasma turbulence has been constructed and studied. The model allows one to investigate the particle acceleration due to the ...

Added: July 19, 2018

Barash L., Marshall J., Weigel M. et al., / Cornell University. Series cond-mat "arxiv.org". 2018. No. 1808.04340.

Estimating the density of states of systems with rugged free energy landscapes is a notoriously difficult task of the utmost importance in many areas of physics ranging from spin glasses to biopolymers to quantum computing. Some of the standard approaches suffer from a spurious convergence of the estimates to metastable minima, and these cases are ...

Added: October 17, 2018

Samodurov V., Kitaeva M. A., Isaev E. et al., Odessa Astronomical Publications 2013 No. 26/2 P. 311-315

Now a day the task of comparative analysis of sample sources from different astronomical catalogs is becoming very topical for astronomers. It is useful both for the same spectral range data and for their cross-analysis for different spectral ranges. It is also important, that the real data from astronomical instruments is placed on-line. For the ...

Added: December 11, 2013

Parkhomenko E., Malova H., Grigorenko E. et al., Physics of Plasmas 2019 Vol. 26 No. 4 P. 1-9

This work is devoted to the investigation of particle acceleration during magnetospheric dipolarizations. A numerical model is presented
taking into account the four scenarios of plasma acceleration that can be realized: (A) total dipolarization with characteristic time scales of
3 min; (B) single peak value of the normal magnetic component Bz occurring on the time scale of ...

Added: April 16, 2019

М. : МИЭМ НИУ ВШЭ, 2013

The materials of The Second International Scientific – Practical Conference is presented below. The Conference reflects the modern state of innovation in education, science, industry and social-economic sphere, from the standpoint of introducing new information technologies.
Digest of Conference materials is presented in 4 parts. It is interesting for a wide range of researchers, teachers, graduate ...

Added: April 18, 2013

Isaev E.A., Kornilov V.V., Samodurov V.A. et al., Odessa Astronomical Publications 2013 Vol. 26 No. 2 P. 308

Modern astronomical research programs need high-speed data transmission. The problem of the development and modernization of local networks and main channels is discussed. ...

Added: December 11, 2013

Пенза : ПГУ, 2016

В сборник трудов включены доклады ХХI-го Международного симпозиума «Надежность и качество», проходившего с 23 по 29 мая 2016 г. в городе Пензе.
Рассмотрены актуальные проблемы теории и практики повышения надежности и качества; эффективности внедрения инновационных и информационных технологий в фундаментальных научных и прикладных исследованиях, образовательных и коммуникативных системах и средах, экономике и юриспруденции; методов и средств ...

Added: May 27, 2016

Ducomet B., Zlotnik A., Zlotnik I. A., / Cornell University. Series math "arxiv.org". 2013. No. arxiv: 1303.3471.

We consider an initial-boundary value problem for a generalized 2D time-dependent Schrödinger equation on a semi-infinite strip. For the Crank-Nicolson finite-difference scheme with approximate or discrete transparent boundary conditions (TBCs), the Strang-type splitting with respect to the potential is applied. For the resulting method, the uniform in time L2-stability is proved. Due to the ...

Added: March 16, 2013

Долгопрудный : МФТИ, 2016

Сборник предназначен для широкого круга специалистов, занимаю- щихся проблемами управления и обработки информации, математическо- го и компьютерного моделирования.
Отражены результаты научных исследований, ведущихся в Москов- ском физико-техническом институте (государственном университете) в области вычислительной математики, математической кибернетики, ком- пьютерных и информационных технологий. ...

Added: October 20, 2018