Chem VSEPR
Linear - 2 double or or 1 triple 1 single bonds with no lone pairs on the central atom, resulting in an angle of 180 degrees.
Trigonal Planar - 3 single or 1 double or 2 single bonds with no lone pairs on central atoms, resulting in an angle of 120 degrees.
Tetrahedral - 4 single bonds and no lone pairs, resulting in an angle of 109.5
Trigonal Pyramidal - 3 single bonds and 1 lone pair on the central atom, resulting in 107.5 degree angle.
Bent 1 - has 2 single bonds and 2 lone pairs on central atom, resulting in 104.5 degree angle.
Trigonal Bipyramid - has 5 single bonds and 2 lone pairs on the central atom, and has no angle degrees.
Octahedral - 6 single bonds and no lone pairs on the central atom, and has no angle degrees.
Bent 2 - has 2 single or 1 double bond and 1 lone pair on the central atom, resulting in a bond angle of less than 120 degrees.
Definicent Octet - does not need full octet.
Be (Beryllium) wants only 2 bonds and no lone pairs. B (Borron) wants only 3 bonds and no lone pairs.
Expanded Octet - more than an octet.
Element has to be in periods 4-7.
A multicentral atom is a central atom bonded to multiple other atoms.