Gaussian 17 Geometry Analysis

A Python tool for checking how Gaussian 17 geometry optimisations may affect molecular structures. It extracts coordinates from tables within .log files and compares which reference atom is closest to a chosen target atom before and after optimisation.

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Usage

python does_structure_change.py <log_directory> <target_atomic_number> <reference_atomic_number>

Example (Br = 35, C = 6):

python does_structure_change.py ./logs 35 6

Show only cases where the closest atom changes:

python does_structure_change.py ./logs 35 6 --only-no

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Output

file1.log: first closest = A#12; after optimisation = A#14; same atom? NO
file2.log: first closest = A#8; after optimisation = A#8; same atom? YES
Total files: 20, total NOs: 7

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Requirements

• Python 3.7+
• No external libraries

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