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Ligand cone angle shows how much space is taken up by a ligand coordinated to a metal center. In coordination chemistry, the ligand cone angle (θ) is a measure of the steric bulk of a ligand in a transition metal coordination complex. It is defined as the solid angle formed with the metal at the vertex of a cone and the outermost edge of the ...
The Tolman electronic parameter (TEP) is a measure of the electron donating or withdrawing ability of a ligand. It is determined by measuring the frequency of the A 1 C-O vibrational mode (ν (CO)) of a (pseudo)-C 3v symmetric complex, [LNi (CO) 3] by infrared spectroscopy, where L is the ligand of interest. [LNi (CO) 3] was chosen as the model ...
The Tolman cone angle and Tolman electronic parameter [3] are named after him. In 1972, he proposed the 16 and 18 electron rule , extending Irving Langmuir 's 18-Electron rule to include the many examples of stable 16 electron square planar d 8 complexes. [ 4 ]
Trimethylphosphine is a highly basic ligand that forms complexes with most metals. As a ligand, trimethylphosphine's Tolman cone angle is 118°. [7] This angle is an indication of the amount of steric protection that this ligand provides to the metal that to which it is bound.
A metal-phosphine complex is a coordination complex containing one or more phosphine ligands. Almost always, the phosphine is an organophosphine of the type R 3 P (R = alkyl, aryl). Metal phosphine complexes are useful in homogeneous catalysis. [ 1 ][ 2 ] Prominent examples of metal phosphine complexes include Wilkinson's catalyst (Rh (PPh 3) 3 ...
In terms of steric bulk, PPh 3 has a Tolman cone angle of 145°, [19] which is intermediate between those of P(C 6 H 11) 3 (170°) and P(CH 3) 3 (115°). In an early application in homogeneous catalysis, NiBr 2 (PPh 3) 2 was used by Walter Reppe for the synthesis of acrylate esters from alkynes, carbon monoxide, and alcohols. [20]
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The Trouton–Noble experiment was an attempt to detect motion of the Earth through the luminiferous aether, and was conducted in 1901–1903 by Frederick Thomas Trouton and H. R. Noble. It was based on a suggestion by George FitzGerald that a charged parallel -plate capacitor moving through the aether should orient itself perpendicular to the ...