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The crystal field stabilization energy (CFSE) is the stability that results from placing a transition metal ion in the crystal field generated by a set of ligands. It arises due to the fact that when the d -orbitals are split in a ligand field (as described above), some of them become lower in energy than before with respect to a spherical ...
John Stanley Griffith and Leslie Orgel [6] championed ligand field theory as a more accurate description of such complexes, although the theory originated in the 1930s with the work on magnetism by John Hasbrouck Van Vleck. Griffith and Orgel used the electrostatic principles established in crystal field theory to describe transition metal ions ...
A spectrochemical series is a list of ligands ordered by ligand "strength", and a list of metal ions based on oxidation number, group and element.For a metal ion, the ligands modify the difference in energy Δ between the d orbitals, called the ligand-field splitting parameter in ligand field theory, or the crystal-field splitting parameter in crystal field theory.
In crystal field theory, d-d transitions that are spin-forbidden are much weaker than spin-allowed transitions. Both can be observed, in spite of the Laporte rule, because the actual transitions are coupled to vibrations that are anti-symmetric and have the same symmetry as the dipole moment operator.
Contract Field Teams, a United States Air Force designed to supplement maintenance of military assets Corps Féminin des Transmissions , part of the Free French forces during World War II United States Army Futures Command's CFTs , each a team of teams, led by a requirements leader, program manager, sustainer, tester
J. H. Van Vleck established the fundamentals of the quantum mechanical theory of magnetism, crystal field theory and ligand field theory (chemical bonding in metal complexes). He is regarded as the Father of Modern Magnetism. [6] [7] [8] During World War II, J. H. Van Vleck worked on radar at the MIT Radiation Lab.
The first step of the reasoning for crystal field theory goes like: "if the metal ion is surrounded by a spherical shell of negative charges, the electrostatic repulsion (between the shell and the electrons of the ions) leads to an increase of the orbitals energy".
Crystal field theory is an alternative description of electronic configurations that is simplified relative to LFT. It rationalizes a number of phenomena, but does not describe bonding nor offer an explanation for why n s electrons are ionized before ( n − 1)d electrons.