14th Group

Carbon (C), Silicon (Si), Germanium (Ge)

Default: CH₄, SiH₄, GeH₄ respectively.
Molecules:
- Neutral atoms Implicit Hydrogens are added to have 4 bonds. 5 or more bonds are forbidden.
- Charged atoms: Every added charge on these atoms (no matter it is positive or negative) decreases by one the number of possible bonds. Maximum charge accepted is ±4.
- Radical: Every added radical on these atoms decreases by one the number accepted of bonds.
- Aromatic compounds: Carbon may form aromatic bonds as well.

Default: Sn
Molecules:
- Neutral atoms: Implicit Hydrogens are added to have 4 bonds (if Tin has at least 1 bond). 5 or 6 bonds are also accepted.
- Charged atoms:
  - Positive charge: Every added charge (no matter it is positive or negative) decreases by one the number of possible bonds. Maximum charge accepted is +4.
  - Negative charge: Not allowed.
- Radical: Every added radical on these atoms decreases by one the number accepted of bonds.
Ions:
- Sn²⁺ and Sn⁴⁺ are accepted.
Other:
- Sn with 2 electrons in bonds and with at least to coordinate bonds are accepted.

Default: Pb
Molecules:
- Neutral atom:
  - 1 or 2 bonds: 1 or 0 implicit hydrogen is added, respectively.
  - 3 or 4 bonds: 1 or 0 implicit hydrogen is added, respectively.
  - 5 or 6 bonds are accepted.
  - More than 6 bonds are forbidden.
- Charged atom:
  - Positive charge: Every added charge (no matter it is positive or negative) decreases by one the number of possible bonds. Maximum charge accepted is +4.
  - Negative charge: Not allowed.
- Radical: Every added radical on these atoms decreases by one the number accepted of bonds.
Ions:
- Pb²⁺ and Pb⁴⁺ are accepted.