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In chemistry, chemical stability is the thermodynamic stability of a chemical system, in particular a chemical compound or a polymer. [1] Colloquially, it may instead refer to kinetic persistence , the shelf-life of a metastable substance or system; that is, the timescale over which it begins to degrade.
In 1923, Peter Debye and Erich Hückel reported the first successful theory for the distribution of charges in ionic solutions. [7] The framework of linearized Debye–Hückel theory subsequently was applied to colloidal dispersions by S. Levine and G. P. Dube [8] [9] who found that charged colloidal particles should experience a strong medium-range repulsion and a weaker long-range attraction.
A common example of metastability in science is isomerisation. Higher energy isomers are long lived because they are prevented from rearranging to their preferred ground state by (possibly large) barriers in the potential energy. During a metastable state of finite lifetime, all state-describing parameters reach and hold stationary values.
Here = = = denotes the Laplacian, which is the quantum kinetic energy operator. At zero temperature, the question is whether the ground state energy (the minimum of the spectrum of H N , K {\displaystyle H_{N,K}} ) is bounded from below by a constant times the total number of particles:
A graph of the potential energy of a bistable system; it has two local minima and .A surface shaped like this with two "low points" can act as a bistable system; a ball resting on the surface can only be stable at those two positions, such as balls marked "1" and "2".
The specific kinetic energy of a system is a crucial parameter in understanding its dynamic behavior and plays a key role in various scientific and engineering applications. Specific kinetic energy is an intensive property, whereas kinetic energy and mass are extensive properties. The SI unit for specific kinetic energy is the joule per ...
In 1997, Tian suggested such a stability condition, which he called K-stability after the K-energy functional introduced by Toshiki Mabuchi. [1] [15] The K originally stood for kinetic due to the similarity of the K-energy functional with the kinetic energy, and for the German kanonisch for the canonical bundle. Tian's definition was analytic ...
The free energy of activation, ΔG ‡, is defined in transition state theory to be the energy such that ‡ = ‡ ′ holds. The parameters ΔH ‡ and ΔS ‡ can then be inferred by determining ΔG ‡ = ΔH ‡ – TΔS ‡ at different temperatures.