TUM Quantum Chemistry Laboratory
Prof. N. Rösch

Exercise 3

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Construct a Z-Matrix for methanol, H3COH, restricting the molecular structure to Cs (a symmetry plane only). As in Exercise 2, the Z-matrix shall preserve symmetry during geometry optimization.

This exercise is more challenging than Exercise 2 since methanol is not planar. Feel free to read some hints. If they are not sufficient you can look at a full solution, too. This solution is only one of several correct alternatives.

Use the following typical estimates for distances and angles:

bond distances, Å C-O 1.4
C-H 1.1
O-H 1.0
bond angle H-C-O tetrahedral angle
C-O-H tetrahedral angle


Atom Distance to atom Angle Dihedral angle
N1 symbol N2 N1-N2 special
N3 N1-N2-N3 special
N4 N1-N2-N3-N4 special
no. no. Å no. degree no. degree

Allowed special options are

Do not use more than one option per parameter. A geometry parameter re-using a fixed value will be fixed automatically.

Z-Matrix as Program Input

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Send in

To have your solution checked, please send in the Z-matrix (Gaussian input) of H3COH restricted to symmetry Cs .

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Copyright © 2003 N. Rösch, Technische Universität München