Molecule disappears on substituting As for P

General Discussion Support
1

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I believe this to be a bug with Avogadro:
Molecule disappears when I try to substitute arsenic for phosphorus

Environment Information

Avogadro version: 1.2.0 downloaded Oct. 7, 2025
Operating system and version: Windows 11

Expected Behavior

Phosphorus atom is replaced by arsenic atom (CHO-PH2 becomes CHO-AsH2)

Actual Behavior

The entire molecule disappears!

Steps to Reproduce

  1. Constructed CHO-PH2 (formylphosphane) without problem
  2. Select arsenic from periodic table (other in draw settings)
  3. Adjust hydrogens is checked
  4. Click on the phosphorus atom.

Please upload files if appropriate here (or via file-sharing service like Dropbox or Pastebin)

untitled.cml (789 Bytes)

2

I can’t support version 1.2. It definitely works for me with v 1.101: Install — Avogadro 1.101.0 documentation

Please give it a try.

3

Which is the newest version? I was intending to download the latest Avogadro 2.

4

The newest release is 1.101, but you can also install a nightly from Install — Avogadro 1.101.0 documentation