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Peter Pulay
Peter Pulay (born September 20, 1941, in Veszprém, Hungary) is a theoretical chemist. He is the Roger B. Bost Distinguished Professor of Chemistry in the Department of Chemistry and Biochemistry at the University of Arkansas, United States. One of his most important contributions is the introduction of the gradient method in quantum chemistry. This allows the prediction of the geometric structure of a molecule using computational chemical programs to be almost routine. He is the main author of the PQS computational chemistry program. His work was cited in the official background material for the 1998 Nobel Prize in chemistry. Among many honors, he was made a Foreign Member of the Hungarian Academy of Sciences in 1993. He is a member of the International Academy of Quantum Molecular Science The International Academy of Quantum Molecular Science (IAQMS) is an international scientific learned society covering all applications of quantum theory to chemistry and chemical physics. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Veszprém
Veszprém (; german: Weißbrunn, sl, Belomost) is one of the oldest urban areas in Hungary, and a city with county rights. It lies approximately north of the Lake Balaton. It is the administrative center of the county (comitatus or 'megye') of the same name. Etymology The name of the city originates from a Slavic personal name ''Bezprem'' or ''Bezprym'' (Proto-Slavic ''Bezprěmъ'') meaning "stubborn", "self-confident, not willing to retreat". ''Besprem'' (before 1002), ''Vezprem'' (1086), ''Bezpremensis'' (1109). The form ''Vezprem'' originates in early medieval scribal habits and frequent exchange of ''B'' and ''V'' under the influence of Greek. The city was named either after a chieftain, or the son of Judith of Hungary, who settled here after her husband Boleslaus I of Poland expelled her and her son. Location and legend The city can be reached via the M7 highway and Road 8. It can also be reached from Győr via Road 82 and from Székesfehérvár via Road 8. Accordin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nobel Prize In Chemistry
) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then "MDCCCXXXIII" above, followed by (smaller) "OB•" then "MDCCCXCVI" below. , awarded_for = Outstanding contributions in chemistry , presenter = Royal Swedish Academy of Sciences , location = Stockholm, Sweden , reward = 9 million SEK (2017) , year = 1901 , holder = Carolyn R. Bertozzi, Morten P. Meldal and Karl Barry Sharpless (2022) , most_awards = Frederick Sanger and Karl Barry Sharpless (2) , website nobelprize.org, previous = 2021 , year2=2022, main=2022, next=2023 The Nobel Prize in Chemistry is awarded annually by the Royal Swedish Academy of Sciences to scientists in the various fields of chemistry. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895, awarded for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1941 Births
Events Below, the events of World War II have the "WWII" prefix. January * January–August – 10,072 men, women and children with mental and physical disabilities are asphyxiated with carbon monoxide in a gas chamber, at Hadamar Euthanasia Centre in Germany, in the first phase of mass killings under the Action T4 program here. * January 1 – Thailand's Prime Minister Plaek Phibunsongkhram decrees January 1 as the official start of the Thai solar calendar new year (thus the previous year that began April 1 had only 9 months). * January 3 – A decree (''Normalschrifterlass'') promulgated in Germany by Martin Bormann, on behalf of Adolf Hitler, requires replacement of blackletter typefaces by Antiqua. * January 4 – The short subject ''Elmer's Pet Rabbit'' is released, marking the second appearance of Bugs Bunny, and also the first to have his name on a title card. * January 5 – WWII: Battle of Bardia in Libya: Australian and British troops def ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Members Of The International Academy Of Quantum Molecular Science
Member may refer to: * Military jury, referred to as "Members" in military jargon * Element (mathematics), an object that belongs to a mathematical set * In object-oriented programming, a member of a class ** Field (computer science), entries in a database ** Member variable, a variable that is associated with a specific object * Limb (anatomy), an appendage of the human or animal body ** Euphemism for penis * Structural component of a truss, connected by nodes * User (computing), a person making use of a computing service, especially on the Internet * Member (geology), a component of a geological formation * Member of parliament * The Members, a British punk rock band * Meronymy, a semantic relationship in linguistics * Church membership, belonging to a local Christian congregation, a Christian denomination and the universal Church * Member, a participant in a club or learned society A learned society (; also learned academy, scholarly society, or academic association) is an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Living People
Related categories * :Year of birth missing (living people) / :Year of birth unknown * :Date of birth missing (living people) / :Date of birth unknown * :Place of birth missing (living people) / :Place of birth unknown * :Year of death missing / :Year of death unknown * :Date of death missing / :Date of death unknown * :Place of death missing / :Place of death unknown * :Missing middle or first names See also * :Dead people * :Template:L, which generates this category or death years, and birth year and sort keys. : {{DEFAULTSORT:Living people 21st-century people People by status ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulay Stress
The Pulay stress or Pulay forces (named for Peter Pulay) is an error that occurs in the stress tensor (or Jacobian matrix) obtained from self-consistent field calculations ( Hartree–Fock or density functional theory) due to the incompleteness of the basis set.Vasp GuideVolume vs. energy, volume relaxations, Pulay Stress/ref> A plane-wave density functional calculation on a crystal with specified lattice vectors will typically include in the basis set all plane waves with energies below the specified energy cutoff. This corresponds to all points on the reciprocal lattice that lie within a sphere whose radius is related to the energy cutoff. Consider what happens when the lattice vectors are varied, resulting in a change in the reciprocal lattice vectors. The points on the reciprocal lattice which represent the basis set will no longer correspond to a sphere, but an ellipsoid. This change in the basis set will result in errors in the calculated ground state energy change. The Pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DIIS
DIIS (direct inversion in the iterative subspace or direct inversion of the iterative subspace), also known as Pulay mixing, is a technique for extrapolating the solution to a set of linear equations by directly minimizing an error residual (e.g. a Newton–Raphson step size) with respect to a linear combination of known sample vectors. DIIS was developed by Peter Pulay in the field of computational quantum chemistry with the intent to accelerate and stabilize the convergence of the Hartree–Fock self-consistent field method. At a given iteration, the approach constructs a linear combination of approximate error vectors from previous iterations. The coefficients of the linear combination are determined so to best approximate, in a least squares sense, the null vector. The newly determined coefficients are then used to extrapolate the function variable for the next iteration. Details At each iteration, an approximate error vector, , corresponding to the variable value, is det ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Academy Of Quantum Molecular Science
The International Academy of Quantum Molecular Science (IAQMS) is an international scientific learned society covering all applications of quantum theory to chemistry and chemical physics. It was created in Menton in 1967. The founding members were Raymond Daudel, Per-Olov Löwdin, Robert G. Parr, John Pople and Bernard Pullman. Its foundation was supported by Louis de Broglie. Originally the Academy had 25 regular members under 65 years of age. This was later raised to 30, and then to 35. There is no limit on the number of members over 65 years of age. The members are "chosen among the scientists of all countries who have distinguished themselves by the value of their scientific work, their role of pioneer or leader of a school in the broad field of quantum chemistry, i.e. the application of quantum mechanics to the study of molecules and macromolecules". The Academy presently consists of 90 members (as of 2006). The Academy organizes the International Congress of Quantum Chemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hungarian Academy Of Sciences
The Hungarian Academy of Sciences ( hu, Magyar Tudományos Akadémia, MTA) is the most important and prestigious learned society of Hungary. Its seat is at the bank of the Danube in Budapest, between Széchenyi rakpart and Akadémia utca. Its main responsibilities are the cultivation of science, dissemination of scientific findings, supporting research and development, and representing Hungarian science domestically and around the world. History The history of the academy began in 1825 when Count István Széchenyi offered one year's income of his estate for the purposes of a ''Learned Society'' at a district session of the Diet in Pressburg (Pozsony, present Bratislava, seat of the Hungarian Parliament at the time), and his example was followed by other delegates. Its task was specified as the development of the Hungarian language and the study and propagation of the sciences and the arts in Hungarian. It received its current name in 1845. Its central building was inaugurate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computational Chemistry
Computational chemistry is a branch of chemistry that uses computer simulation to assist in solving chemical problems. It uses methods of theoretical chemistry, incorporated into computer programs, to calculate the structures and properties of molecules, groups of molecules, and solids. It is essential because, apart from relatively recent results concerning the hydrogen molecular ion (dihydrogen cation, see references therein for more details), the quantum many-body problem cannot be solved analytically, much less in closed form. While computational results normally complement the information obtained by chemical experiments, it can in some cases predict hitherto unobserved chemical phenomena. It is widely used in the design of new drugs and materials. Examples of such properties are structure (i.e., the expected positions of the constituent atoms), absolute and relative (interaction) energies, electronic charge density distributions, dipoles and higher multipole moments, vi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kingdom Of Hungary (1920–1946)
The Kingdom of Hungary ( hu, Magyar Királyság), sometimes referred to as the Regency or the Horthy era, existed as a country from 1920 to 1946 under the rule of Regent Miklós Horthy, who nominally represented the Hungarian monarchy. In reality there was no king, and attempts by King Charles IV to return to the throne shortly before his death were prevented by Horthy. Hungary under Horthy was characterized by its conservative, nationalist and fiercely anti-communist character. The government was based on an unstable alliance of conservatives and right-wingers. Foreign policy was characterized by revisionism — the total or partial revision of the Treaty of Trianon, which had seen Hungary lose over 70% of its historic territory along with over three million Hungarians, who mostly lived in the border territories outside the new borders of the kingdom. Hungary's interwar politics were dominated by an obsession with the territorial losses suffered in this treaty, with the resen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PQS (chemical)
PQS is a general purpose quantum chemistry program. Its roots go back to the first ab initio gradient program developed in Professor Peter Pulay's group but now it is developed and distributed commercially by Parallel Quantum Solutions. There is a reduction in cost for academic users and a site license. Its strong points are geometry optimization, NMR chemical shift calculations, and large MP2 calculations, and high parallel efficiency on computing clusters. It includes many other capabilities including Density functional theory, the semiempirical methods, MINDO/3, MNDO, AM1 and PM3, Molecular mechanics using the SYBYL 5.0 Force Field, the quantum mechanics/molecular mechanics mixed method using the ONIOM method, natural bond orbital (NBO) analysis and COSMO solvation models. Recently, a highly efficient parallel CCSD(T) code for closed shell systems has been developed. This code includes many other post Hartree–Fock methods: MP2, MP3, MP4, CISD, CEPA, QCISD and so o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
