Z-Matrix for a Polyatomic Molecule

2 Z-MATRIX FOR A POLYATOMIC MOLECULE Here is a Z-matrix for a formaldehyde molecule  

FIGURE 9.1 Illustration of the formaldehyde Z-matrix example, (a) First three atoms and associated variables, (b) Dihedral angle. 

Line 1 C indicates that the first atom is a carbon. 

Line 2 O 1 OC indicates that the second atom is an oxygen with a distance of OC to the first atom. 

Line 3 H 1 HC 2 A indicates that the third atom is a hydrogen with a distance of HC to the first atom and an angle between the third, first, and second atoms of A (in degrees). 

Line 5 There must be a blank line between the list of atoms and the list of variables. 

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