In
chemistry, the capped square antiprismatic molecular geometry describes the shape of compounds where nine atoms, groups of atoms, or
ligand
In coordination chemistry, a ligand is an ion or molecule ( functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's elec ...
s are arranged around a central atom, defining the vertices of a
gyroelongated square pyramid.
The gyroelongated square pyramid is a
square pyramid with a
square antiprism
In geometry, the square antiprism is the second in an infinite family of antiprisms formed by an even-numbered sequence of triangle sides closed by two polygon caps. It is also known as an ''anticube''.
If all its faces are regular, it is a sem ...
connected to the square base. In this respect, it can be seen as a "capped" square antiprism (a square antiprism with a pyramid erected on one of the square faces).
It is very similar to the
tricapped trigonal prismatic molecular geometry, and there is some dispute over the specific geometry exhibited by certain molecules.
Examples
*
is sometimes described as having a capped square antiprismatic geometry, although its geometry is most often described as tricapped trigonal prismatic.
*, a
lanthanum
Lanthanum is a chemical element with the symbol La and atomic number 57. It is a soft, ductile, silvery-white metal that tarnishes slowly when exposed to air. It is the eponym of the lanthanide series, a group of 15 similar elements between lant ...
(III) complex with a La–La bond.
References
Stereochemistry
Molecular geometry
{{chemistry-stub