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Electron Localization Function
In quantum chemistry, the electron localization function (ELF) is a measure of the likelihood of finding an electron in the neighborhood space of a reference electron located at a given point and with the same Spin (physics), spin. Physically, this measures the extent of spatial localization of the reference electron and provides a method for the mapping of electron pair probability in multielectronic systems. ELF's usefulness stems from the observation that it allows electron localization to be analyzed in a chemically intuitive way. For example, the Electron shell, shell structure of heavy atoms is obvious when plotting ELF against the radial distance from the nucleus; the ELF for radon has six clear Maxima and minima, maxima, whereas the electronic density decreases Monotonic function, monotonically and the radially weighted density fails to show all shells. When applied to molecules, an analysis of the ELF shows a clear separation between the Core electron, core and valence el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Localization Function Of Kr (HF Cc-pV5Z)
The electron (, or in nuclear reactions) is a subatomic particle with a negative one elementary charge, elementary electric charge. It is a fundamental particle that comprises the ordinary matter that makes up the universe, along with up quark, up and down quark, down quarks. Electrons are extremely lightweight particles that orbit the positively charged atomic nucleus, nucleus of atoms. Their negative charge is balanced by the positive charge of protons in the nucleus, giving atoms their overall electric charge#Charge neutrality, neutral charge. Ordinary matter is composed of atoms, each consisting of a positively charged nucleus surrounded by a number of orbiting electrons equal to the number of protons. The configuration and energy levels of these orbiting electrons determine the chemical properties of an atom. Electrons are bound to the nucleus to different degrees. The outermost or valence electron, valence electrons are the least tightly bound and are responsible for th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elf H2o
An elf (: elves) is a type of humanoid supernatural being in Germanic folklore. Elves appear especially in North Germanic mythology, being mentioned in the Icelandic ''Poetic Edda'' and the ''Prose Edda''. In medieval Germanic-speaking cultures, elves were thought of as beings with magical powers and supernatural beauty, ambivalent towards everyday people and capable of either helping or hindering them. Beliefs varied considerably over time and space and flourished in both pre-Christian and Christian cultures. The word ''elf'' is found throughout the Germanic languages. It seems originally to have meant 'white being'. However, reconstructing the early concept depends largely on texts written by Christians, in Old and Middle English, medieval German, and Old Norse. These associate elves variously with the gods of Norse mythology, with causing illness, with magic, and with beauty and seduction. After the medieval period, the word ''elf'' became less common throughout th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charge Density
In electromagnetism, charge density is the amount of electric charge per unit length, surface area, or volume. Volume charge density (symbolized by the Greek letter ρ) is the quantity of charge per unit volume, measured in the SI system in coulombs per cubic meter (C⋅m−3), at any point in a volume. Surface charge density (σ) is the quantity of charge per unit area, measured in coulombs per square meter (C⋅m−2), at any point on a surface charge distribution on a two dimensional surface. Linear charge density (λ) is the quantity of charge per unit length, measured in coulombs per meter (C⋅m−1), at any point on a line charge distribution. Charge density can be either positive or negative, since electric charge can be either positive or negative. Like mass density, charge density can vary with position. In classical electromagnetic theory charge density is idealized as a '' continuous'' scalar function of position \boldsymbol, like a fluid, and \rho(\boldsymbo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Bader
Richard F. W. Bader (October 15, 1931 – January 15, 2012) was a Canadian quantum chemist, noted for his work on the atoms in molecules theory. This theory attempts to establish a physical basis for many of the working concepts of chemistry, such as atoms in molecules and bonding, in terms of the topology of the electron density function in three-dimensional space. Alongside the eminent chemist Ronald Gillespie, he had a significant influence on inorganic chemistry education in Canada. He was born in 1931 in Kitchener, Ontario, Canada. His parents were Albert Bader and Alvina Bader, who immigrated from Switzerland. His father was a butcher at Burns Pride of Canada and his mother was a housekeeper at Kitchener Hospital of Waterloo. He received a scholarship from McMaster University that allowed him to earn a BSC in 1953. His father was his best supporter who encouraged him and taught him to "never quit" his education and his dream. He finished his master's degree in science ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Differential Topology
In mathematics, differential topology is the field dealing with the topological properties and smooth properties of smooth manifolds. In this sense differential topology is distinct from the closely related field of differential geometry, which concerns the ''geometric'' properties of smooth manifolds, including notions of size, distance, and rigid shape. By comparison differential topology is concerned with coarser properties, such as the number of holes in a manifold, its homotopy type, or the structure of its diffeomorphism group. Because many of these coarser properties may be captured algebraically, differential topology has strong links to algebraic topology. The central goal of the field of differential topology is the classification of all smooth manifolds up to diffeomorphism. Since dimension is an invariant of smooth manifolds up to diffeomorphism type, this classification is often studied by classifying the ( connected) manifolds in each dimension separately: * In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andreas Savin
Andreas () is a name derived from the Greek noun ἀνήρ ''anēr'', with genitive ἀνδρός ''andros'', which means "man". See the article on Andrew for more information. The Scandinavian name is earliest attested as antreos in a runestone from the 12th century. The name Andrea may be used as a feminine form, but it is also the main masculine form in Italy and the canton of Ticino in Switzerland. Given name Andreas is a common name, and this is not a comprehensive list of articles on people named Andreas. See instead . Surname * Alfred T. Andreas (1939–1900), American publisher and historian * Casper Andreas (born 1972), American actor and film director * Dwayne Andreas (1918–2016), American businessman * Harry Andreas (1879–1955), Australian businessman and company director * Lisa Andreas (born 1987), English singer Places * Andreas, Isle of Man, a village and parish in the Isle of Man See also * San Andreas (other) References * – Diction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Density Functional Theory
Density functional theory (DFT) is a computational quantum mechanical modelling method used in physics, chemistry and materials science to investigate the electronic structure (or nuclear structure) (principally the ground state) of many-body systems, in particular atoms, molecules, and the condensed phases. Using this theory, the properties of a many-electron system can be determined by using functionals - that is, functions that accept a function as input and output a single real number. In the case of DFT, these are functionals of the spatially dependent electron density. DFT is among the most popular and versatile methods available in condensed-matter physics, computational physics, and computational chemistry. DFT has been very popular for calculations in solid-state physics since the 1970s. However, DFT was not considered accurate enough for calculations in quantum chemistry until the 1990s, when the approximations used in the theory were greatly refined to better m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimensionless
Dimensionless quantities, or quantities of dimension one, are quantities implicitly defined in a manner that prevents their aggregation into units of measurement. ISBN 978-92-822-2272-0. Typically expressed as ratios that align with another system, these quantities do not necessitate explicitly defined units. For instance, alcohol by volume (ABV) represents a volumetric ratio; its value remains independent of the specific units of volume used, such as in milliliters per milliliter (mL/mL). The number one is recognized as a dimensionless base quantity. Radians serve as dimensionless units for angular measurements, derived from the universal ratio of 2π times the radius of a circle being equal to its circumference. Dimensionless quantities play a crucial role serving as parameters in differential equations in various technical disciplines. In calculus, concepts like the unitless ratios in limits or derivatives often involve dimensionless quantities. In differential geom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uniform Electron Gas
Jellium, also known as the uniform electron gas (UEG) or homogeneous electron gas (HEG), is a quantum mechanical model of interacting free electrons in a solid where the complementary positive charges are not atomic nuclei but instead an idealized background of uniform positive charge density. This model allows one to focus on the effects in solids that occur due to the quantum nature of electrons and their mutual repulsive interactions (due to like charge) without explicit introduction of the atomic lattice and structure making up a real material. Jellium is often used in solid-state physics as a simple model of delocalized electrons in a metal, where it can qualitatively reproduce features of real metals such as screening, plasmons, Wigner crystallization and Friedel oscillations. At zero temperature, the properties of jellium depend solely upon the constant electronic density. This property lends it to a treatment within density functional theory; the formalism itself pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boson
In particle physics, a boson ( ) is a subatomic particle whose spin quantum number has an integer value (0, 1, 2, ...). Bosons form one of the two fundamental classes of subatomic particle, the other being fermions, which have half odd-integer spin (1/2, 3/2, 5/2, ...). Every observed subatomic particle is either a boson or a fermion. Paul Dirac coined the name ''boson'' to commemorate the contribution of Satyendra Nath Bose, an Indian physicist. Some bosons are elementary particles occupying a special role in particle physics, distinct from the role of fermions (which are sometimes described as the constituents of "ordinary matter"). Certain elementary bosons (e.g. gluons) act as force carriers, which give rise to forces between other particles, while one (the Higgs boson) contributes to the phenomenon of mass. Other bosons, such as mesons, are composite particles made up of smaller constituents. Outside the realm of particle physics, multiple identical composite bosons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
