Frequently Asked Question

To combine the Z matrices of two different molecules, you can use the following steps:

1. Orient the two molecules so that their centers of mass are coincident.
2. Translate one molecule so that its origin is at the center of mass of the other molecule.
3. Rotate one molecule so that its principal axes are aligned with the principal axes of the other molecule.
4. Add the corresponding elements of the two Z matrices to obtain the Z matrix of the combined molecule.

In your case, ethene has 6 atoms and cyclopentane has 10 atoms, so the combined molecule will have 16 atoms. The Z matrix for ethene is:
0.000000 0.000000 0.000000
0.607962 0.707107 0.000000
-0.607962 0.707107 0.000000
0.000000 -1.414214 0.000000
And the Z matrix for cyclopentane is:
0.000000 0.000000 0.000000
1.513969 0.000000 0.000000
-0.756985 1.306980 0.000000
-0.756985 -1.306980 0.000000
1.513969 0.000000 1.147285
1.513969 0.000000 -1.147285
-0.756985 1.306980 1.147285
-0.756985 -1.306980 1.147285
-0.756985 1.306980 -1.147285
-0.756985 -1.306980 -1.147285
The Z matrix for the combined molecule is then:
0.000000 0.000000 0.000000
0.607962 0.707107 0.000000
-0.607962 0.707107 0.000000
0.000000 -1.414214 0.000000
1.513969 0.000000 0.000000
-0.756985 1.306980 0.000000
-0.756985 -1.306980 0.000000
1.513969 0.000000 1.147285
1.513969 0.000000 -1.147285
-0.756985 1.306980 1.147285
-0.756985 -1.306980 1.147285
-0.756985 1.306980 -1.147285
-0.756985 -1.306980 -1.147285