molecule mass
121High-performance liquid chromatography — An HPLC. From left to right: A pumping device generating a gradient of two different solvents, a steel enforced column and an apparatus for measuring the absorbance. Acronym HPLC Classification Chromatography …
122Organic chemistry — Structure of the methane molecule: the simplest hydrocarbon compound. Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation (by synthesis or by… …
123Protein — Proteins are large organic compounds made of amino acids arranged in a linear chain and joined together by peptide bonds between the carboxyl and amino groups of adjacent amino acid residues. The sequence of amino acids in a protein is defined by …
124Born-Oppenheimer approximation — In quantum chemistry, the computation of the energy and wavefunction of an average size molecule is a formidable task that is alleviated by the Born Oppenheimer (BO) approximation. For instance the benzene molecule consists of 12 nuclei and 42… …
125Rigid rotor — The rigid rotor is a mechanical model that is used to explain rotating systems. An arbitrary rigid rotor is a 3 dimensional rigid object, such as a top. To orient such an object in space three angles are required. A special rigid rotor is the… …
126Eckart conditions — The Eckart conditions, [ C. Eckart, Some studies concerning rotating axes and polyatomic molecules , Physical Review,vol. 47, pp. 552 558 (1935).] named after Carl Eckart, sometimes referred to as Sayvetz conditions, [Aaron Sayvetz, The Kinetic… …
127electromagnetic radiation — Physics. radiation consisting of electromagnetic waves, including radio waves, infrared, visible light, ultraviolet, x rays, and gamma rays. [1950 55] * * * Energy propagated through free space or through a material medium in the form of… …
128evolution — evolutional, adj. evolutionally, adv. /ev euh looh sheuhn/ or, esp. Brit., /ee veuh /, n. 1. any process of formation or growth; development: the evolution of a language; the evolution of the airplane. 2. a product of such development; something… …
