Solid angle#
Ligand solid angle and solid cone angles are implemented with a numerical recipe as described by Guzei and Wendt [1].
Module#
The SolidAngle class is provided to calculate and store the solid angles.
>>> from morfeus import SolidAngle, read_xyz
>>> elements, coordinates = read_xyz("phosphines/PdPMe3.xyz")
>>> solid_angle = SolidAngle(elements, coordinates, 1)
>>> print(solid_angle.cone_angle)
112.53614024551955
>>> print(solid_angle.solid_angle)
2.794082404625142
>>> print(solid_angle.G)
22.234601305109027
>>> solid_angle.print_report()
Solid angle (sr): 2.794
Cone angle (°): 112.536
G: 22.235
The Bondi vdW radii are used in reference [2], but
radii from the CRC Handbook is the default here. It can be changed with
radii_type=<str>. Custom radii can passed with radii=<list>. The units
for the solid cone angle are in degrees, steradians for the solid angle and the
G parameter is in percent.
For more detailed information, use help(SolidAngle) or see the API:
SolidAngle.
Command line script#
The command line script provides access to the basic functionality through the terminal.
$ morfeus solid_angle PdPMe3.xyz - 1 - print_report
Solid angle (sr): 2.794
Cone angle (°): 112.536
G: 22.235
Background#
The ligand solid angle, Ω is the solid angle of the complete shadow cast by a ligand when hypothetically illuminated from the metal center. [2] From Ω, a solid “cone” angle Θ can also be calculated, which is analogous to Tolman’s cone angle. The G parameter is a measure of how much of the metal coordination sphere is shielded by the ligands. [1]
ᴍᴏʀғᴇᴜs uses a numerical method, in a similar way to the Solid-G program, but with different radii. The results have been benchmarked against the exact solid angle program by Allen and co-workers, [2] and agree within numerical accuracy.
References