Calculator Inputs
Use the form to calculate a complex ion charge directly or solve the metal oxidation state from a known overall charge.
Example Data Table
| Complex | Metal Oxidation State | Ligand Charge Total | Net Charge | Coordination Sites | Notes |
|---|---|---|---|---|---|
| [Fe(CN)6] | 3+ | 6- | 3- | 6 | Hexacyanoferrate example with six monodentate ligands. |
| [Co(NH3)6] | 3+ | 0 | 3+ | 6 | Neutral ammine ligands leave the metal state unchanged. |
| [CuCl4] | 2+ | 4- | 2- | 4 | Four chloride ligands generate an anionic complex. |
| [Ni(en)3] | 2+ | 0 | 2+ | 6 | Three bidentate ethylenediamine ligands create six coordination sites. |
| [PtCl6] | 4+ | 6- | 2- | 6 | Classic octahedral halide coordination example. |
Formula Used
Complex charge formula
Complex Charge = Metal Oxidation State + Σ(Ligand Charge × Ligand Count)
Metal oxidation state formula
Metal Oxidation State = Complex Charge - Σ(Ligand Charge × Ligand Count)
Coordination sites estimate
Coordination Sites = Σ(Ligand Denticity × Ligand Count)
This calculator adds the metal contribution and all ligand charge contributions. Neutral ligands contribute zero charge, while anionic and cationic ligands change the final net charge.
How to Use This Calculator
- Select whether you want to calculate the complex ion charge or solve the metal oxidation state.
- Enter the complex label and the metal symbol or metal name.
- Provide the metal oxidation state when calculating charge, or enter the known overall complex charge when solving the metal state.
- Fill in each ligand row with ligand name, charge, count, and denticity.
- Use zero count for unused ligand rows.
- Press Submit to display the result above the form.
- Review the summary cards, equation, table, and graph.
- Use the CSV and PDF buttons to export the output.
FAQs
1. What does this calculator determine?
It determines the net charge of a coordination complex or solves the metal oxidation state when the overall charge is already known. It also estimates coordination sites from denticity and ligand count.
2. How are neutral ligands treated?
Neutral ligands such as NH3, H2O, and en contribute zero net charge. They still affect coordination site count when they bind, especially when they are multidentate.
3. Why is denticity included?
Denticity does not change the complex charge directly. It helps estimate how many donor sites are occupied, which is useful for interpreting coordination number and ligand binding pattern.
4. Can I enter negative metal oxidation states?
Yes. The form accepts whole-number oxidation states, including negative values. That supports uncommon but valid cases in organometallic or electron-rich coordination chemistry.
5. What if I only know the complex charge?
Choose the mode that solves the metal oxidation state. Enter the known overall complex charge and the ligand data, and the calculator rearranges the charge-balance equation automatically.
6. Does the calculator check geometry or stability?
No. It focuses on formal charge balance and coordination-site estimation. Geometry, spin state, ligand field effects, and thermodynamic stability require separate chemical analysis.
7. Why can the final charge be zero?
A neutral coordination complex forms when the metal oxidation state and the total ligand charge cancel perfectly. In that case, the complex has no net ionic charge.
8. Can I export the result for reporting?
Yes. After calculation, use the CSV button for spreadsheet-ready output or the PDF button for a formatted report containing the summary, equation, and charge breakdown table.