Search results
Results From The WOW.Com Content Network
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 van der Waals spheres of the ligand atoms at the perimeter of the base of the cone.
The natural bite angle (β n) of diphosphines, obtained using molecular mechanics calculations, is defined as the preferred chelation angle determined only by ligand backbone and not by metal valence angles (Figure 3). [1] Figure 3. Bite angle of a diphosphine ligand bound to rhodium.
The user may choose to replace the inclination angle by its complement, the elevation angle (or altitude angle), measured upward between the reference plane and the radial line—i.e., from the reference plane upward (towards to the positive z-axis) to the radial line. The depression angle is the negative of the elevation angle.
The bond order of the metal ligand bond can be in part distinguished through the metal ligand bond angle (M−X−R). This bond angle is often referred to as being linear or bent with further discussion concerning the degree to which the angle is bent. For example, an imido ligand in the ionic form has three lone pairs.
Euler angles, normally in the Tait–Bryan convention, are also used in robotics for speaking about the degrees of freedom of a wrist. They are also used in electronic stability control in a similar way. Gun fire control systems require corrections to gun-order angles (bearing and elevation) to compensate for deck tilt (pitch and roll).
The angle between the two Cp rings is fixed. Rotation of the rings about the metal-centroid axis is stopped as well. A related class of derivatives give rise to the constrained geometry complexes. In these cases, a Cp ligand as linked to a non-Cp ligand. Such complexes have been commercialized for the production of polypropylene.
Commonly used as a ligand in organometallic chemistry, it is often abbreviated to PCy 3, where Cy stands for cyclohexyl. It is characterized by both high basicity (pK a = 9.7) [1] and a large ligand cone angle (170°). [2] [3]
It is used as a bidentate diphosphine ligand and is noteworthy for having a particularly wide bite angle (108°). [1] Such ligands are useful in the hydroformylation of alkenes. [2] Illustrative of its wide bite angle, it forms both cis and trans adducts of platinum(II) chloride. In the latter context, xantphos is classified as a trans-spanning ...