|
Lennard-Jones
Sir John Edward Lennard-Jones (27 October 1894 – 1 November 1954) was a British mathematician and professor of theoretical physics at the University of Bristol, and then of theoretical science at the University of Cambridge. He was an important pioneer in the development of modern computational chemistry and theoretical chemistry. Early life and education Lennard-Jones was born on 27 October 1894 at Leigh, Lancashire, the eldest son of Mary Ellen and Hugh Jones, an insurance agent. He was educated at Leigh Grammar School, going on to study at the University of Manchester, graduating in 1915 with a first-class honours degree in mathematics. Career Lennard-Jones is well known among scientists for his work on molecular structure, valency and intermolecular forces. Much research of these topics over several decades grew from a paper he published in 1929. His theories of liquids and of surface catalysis also remain influential. He wrote few, albeit influential, papers. His ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lennard-Jones Potential
The Lennard-Jones potential (also termed the LJ potential or 12-6 potential) is an intermolecular pair potential. Out of all the intermolecular potentials, the Lennard-Jones potential is probably the one that has been the most extensively studied. It is considered an archetype model for simple yet realistic intermolecular interactions. The Lennard-Jones potential models soft repulsive and attractive ( van der Waals) interactions. Hence, the Lennard-Jones potential describes electronically neutral atoms or molecules. It is named after John Lennard-Jones. The commonly used expression for the Lennard-Jones potential is V_\text(r) = 4\varepsilon \left \left(\frac\right)^ - \left(\frac\right)^6 \right, where r is the distance between two interacting particles, \varepsilon is the depth of the potential well (usually referred to as 'dispersion energy'), and \sigma is the distance at which the particle-particle potential energy V is zero (often referred to as 'size of the particle'). Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samuel Francis Boys
Samuel Francis (Frank) Boys (20 December 1911 – 16 October 1972) was a British theoretical chemist. Education Boys was born in Pudsey, Yorkshire, England. He was educated at the Grammar School in Pudsey and then at Imperial College London. He graduated in Chemistry in 1932. He was awarded a PhD in 1937 from Cambridge for research conducted at Trinity College, supervised first by Martin Lowry, and then, after Lowry's 1936 death, by John Lennard-Jones. His thesis was "The Quantum Theory of Optical Rotation". Career In 1938, Boys was appointed an Assistant Lecturer in Mathematical Physics at Queen's University Belfast. He spent the whole of the Second World War working on explosives research with the Ministry of Supply at the Royal Arsenal, Woolwich, with Lennard-Jones as his supervisor. After the war, Boys accepted an ICI Fellowship at Imperial College, London. In 1949, he was appointed to a Lectureship in theoretical chemistry at the University of Cambridge. He remained ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Bristol
The University of Bristol is a Red brick university, red brick Russell Group research university in Bristol, England. It received its royal charter in 1909, although it can trace its roots to a Society of Merchant Venturers, Merchant Venturers' school founded in 1595 and University College, Bristol, which had been in existence since 1876. Bristol is organised into #Academic structure, six academic faculties composed of multiple schools and departments running over 200 undergraduate courses, largely in the Tyndalls Park area of the city. The university had a total income of £752.0 million in 2020–21, of which £169.8 million was from research grants and contracts. It is the largest independent employer in Bristol. Current academics include 21 fellows of the Academy of Medical Sciences, 13 fellows of the British Academy, 13 fellows of the Royal Academy of Engineering and 44 fellows of the Royal Society. Among alumni and faculty, the university counts 9 Nobel laureates. Bristol is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Coulson
Charles Alfred Coulson (13 December 1910 – 7 January 1974) was a British applied mathematician and theoretical chemist. Coulson's major scientific work was as a pioneer of the application of the quantum theory of valency to problems of molecular structure, dynamics and reactivity. He was also a Methodist lay preacher, served on the World Council of Churches from 1962 to 1968, and was chairman of Oxfam from 1965 to 1971. Early life The parents of Charles Coulson and his younger twin brother John Metcalfe Coulson were educators who hailed from the Midlands. The twins were born when their father, Alfred, was principal of Dudley Technical College and superintendent of the Methodist Sunday School, and their mother Annie Sincere Hancock was Headmistress of Tipton Elementary School, close by. Coulson's parents maintained a religious Methodist home. When the Coulson brothers were 10, their father was appointed Superintendent of Technical Colleges for the South-West of England ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keele University
Keele University, officially known as the University of Keele, is a public research university in Keele, approximately from Newcastle-under-Lyme, Staffordshire, England. Founded in 1949 as the University College of North Staffordshire, Keele was granted university status by Royal Charter in 1962. Keele occupies a rural campus close to the village of Keele and consists of extensive woods, lakes and Keele Hall set in Staffordshire Potteries. It has a science park and a conference centre, making it the largest campus university in the UK. The university's School of Medicine operates the clinical part of its courses from a separate campus at the Royal Stoke University Hospital. The School of Nursing and Midwifery is based at the nearby Clinical Education Centre. History Establishment Cambridge and Oxford Extension Lectures had been arranged in the Potteries since the 1890s, but outside any organised educational framework or establishment. In 1904, funds were raised by l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermolecular Force
An intermolecular force (IMF) (or secondary force) is the force that mediates interaction between molecules, including the electromagnetic forces of attraction or repulsion which act between atoms and other types of neighbouring particles, e.g. atoms or ions. Intermolecular forces are weak relative to intramolecular forces – the forces which hold a molecule together. For example, the covalent bond, involving sharing electron pairs between atoms, is much stronger than the forces present between neighboring molecules. Both sets of forces are essential parts of force fields frequently used in molecular mechanics. The investigation of intermolecular forces starts from macroscopic observations which indicate the existence and action of forces at a molecular level. These observations include non-ideal-gas thermodynamic behavior reflected by virial coefficients, vapor pressure, viscosity, superficial tension, and absorption data. The first reference to the nature of microscopic f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid
A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, and plasma), and is the only state with a definite volume but no fixed shape. A liquid is made up of tiny vibrating particles of matter, such as atoms, held together by intermolecular bonds. Like a gas, a liquid is able to flow and take the shape of a container. Most liquids resist compression, although others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly constant density. A distinctive property of the liquid state is surface tension, leading to wetting phenomena. Water is by far the most common liquid on Earth. The density of a liquid is usually close to that of a solid, and much higher than that of a gas. Therefore, liquid and solid are both termed condensed matter. O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ralph Howard Fowler
Sir Ralph Howard Fowler (17 January 1889 – 28 July 1944) was a British physicist and astronomer. Education Fowler was born at Roydon, Essex, on 17 January 1889 to Howard Fowler, from Burnham, Somerset, and Frances Eva, daughter of George Dewhurst, a cotton merchant from Manchester. He was initially educated at home, going on to attend Evans' preparatory school at Horris Hill and Winchester College. He won a scholarship to Trinity College, Cambridge and studied mathematics, becoming a wrangler in Part II of the Mathematical Tripos. War service In World War I he obtained a commission in the Royal Marine Artillery and was seriously wounded in his shoulder in the Gallipoli campaign. The wound enabled his friend Archibald Hill to use his talents properly. As Hill's second in command he worked on anti-aircraft ballistics in the Anti-Aircraft Experimental Section of HMS ''Excellent'' on Whale Island. He made a major contribution on the aerodynamics of spinning shells. He was a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Pople
Sir John Anthony Pople (31 October 1925 – 15 March 2004) was a British theoretical chemist who was awarded the Nobel Prize in Chemistry with Walter Kohn in 1998 for his development of computational methods in quantum chemistry. Early life and education Pople was born in Burnham-on-Sea, Somerset, and attended the Bristol Grammar School. He won a scholarship to Trinity College, Cambridge, in 1943. He received his Bachelor of Arts degree in 1946. Between 1945 and 1947 he worked at the Bristol Aeroplane Company. He then returned to the University of Cambridge and was awarded his PhD in mathematics in 1951 on lone pair electrons. Career After obtaining his PhD, he was a research fellow at Trinity College, Cambridge and then from 1954 a lecturer in the mathematics faculty at Cambridge. In 1958, he moved to the National Physical Laboratory, near London as head of the new basics physics division. He moved to the United States of America in 1964, where he lived the rest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Davy Medal
The Davy Medal is awarded by the Royal Society of London "for an outstandingly important recent discovery in any branch of chemistry". Named after Humphry Davy, the medal is awarded with a monetary gift, initially of £1000 (currently £2000). History The medal was first awarded in 1877 to Robert Wilhelm Bunsen and Gustav Robert Kirchhoff "for their researches & discoveries in spectrum analysis", and has since been awarded 140 times. The medal is awarded annually and, unlike other Royal Society medals (such as the Hughes), has been awarded without interruption since its inception. The medal has been awarded to multiple individuals in the same year: in 1882, for example, it was awarded to Dmitri Mendeleev and Julius Lothar Meyer "for their discovery of the periodic relations of the atomic weights"; in 1883 to Marcellin Berthelot and Julius Thomsen "for their researches in thermo-chemistry"; in 1893 to Jacobus Henricus van 't Hoff and Joseph Achille Le Bel "In recognition of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Combination Of Atomic Orbitals
A linear combination of atomic orbitals or LCAO is a quantum superposition of atomic orbitals and a technique for calculating molecular orbitals in quantum chemistry. In quantum mechanics, electron configurations of atoms are described as wavefunctions. In a mathematical sense, these wave functions are the basis set of functions, the basis functions, which describe the electrons of a given atom. In chemical reactions, orbital wavefunctions are modified, i.e. the electron cloud shape is changed, according to the type of atoms participating in the chemical bond. It was introduced in 1929 by Sir John Lennard-Jones with the description of bonding in the diatomic molecules of the first main row of the periodic table, but had been used earlier by Linus Pauling for H2+. Mathematical description An initial assumption is that the number of molecular orbitals is equal to the number of atomic orbitals included in the linear expansion. In a sense, ''n'' atomic orbitals combine to f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leigh, Lancashire
Leigh is a town in the Metropolitan Borough of Wigan, Greater Manchester, England, on low-lying land northwest of Chat Moss. Within the boundaries of the historic county of Lancashire, Leigh was originally the centre of a large ecclesiastical parish covering six vills or townships. When the three townships of Pennington, Westleigh and Bedford merged in 1875, forming the Leigh Local Board District, Leigh became the official name for the town, although it had been applied to the area of Pennington and Westleigh around the parish church for many centuries. The town became an urban district in 1894 when part of Atherton was added. In 1899 Leigh became a municipal borough. The first town hall was built on King Street and replaced by the present building in 1907. Originally an agricultural area (noted for dairy farming), domestic spinning and weaving led to a considerable silk industry and, in the 20th century, the cotton industry. Leigh also exploited the underlying coal measures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
