It's not up to me to add

It's not up to me to add anything to the databases that Molecules searches. Currently, the application searches the NCBI PubChem repository (for smaller molecules) and the RCSB Protein Data Bank (for proteins and larger biomolecules). These are taxpayer-funded central databases of molecular structures, and I merely search and download structures from those databases. Aside from my interactions with their scientists and programmers, I have no affiliation with these resources, so I can't dictate what they have in their databases.

However, Molecules does also support the loading of custom structures via iTunes. If you can find PDB format files of the structures you describe, you can use iTunes File Sharing to copy these molecular structures into the application and have it render them. This ca be done by connecting your device to iTunes, going to that device's listing, navigating to the Apps tab, and scrolling down until you find the entry for Molecules under File Sharing. Click on that entry and you should be able to drag files into the application from your local filesystem.

Sunset Lake Software - Comments for "Basic VSEPR shapes"

It's not up to me to add