Tungsten Oxidation States

Reference for all known oxidation states of tungsten (W, element 74), with +6 dominant, real compound examples for each state, electron configuration, and physical properties.

Atomic # 74 W Tungsten
Atomic Mass
183.84 u
Group
6 (VIB)
Period
6
Block
d-block
Electronegativity
2.36 (Pauling)
Oxidation States
−2 to +6 (+6 dominant)

Tungsten has an exceptionally wide oxidation state range, from −2 to +6. The +6 state dominates in ordinary chemistry — it corresponds to losing all six valence electrons (5d4 6s2), which is strongly stabilized by bonding with highly electronegative ligands such as O and F. Lower states appear in reduced oxides, halides, chalcogenides, and organometallic carbonyl complexes.

State Stability Example Notes
+6 Dominant WO3, WF6, WO4²⁻ Most common state in all ordinary compounds. Full loss of 5d46s2 electrons. Tungstate ion (WO4²⁻) is an important industrial species.
+5 Stable WCl5, W2O5 One d-electron retained. Often forms dinuclear W–W bonded species. WCl5 is a useful synthetic precursor.
+4 Stable WO2, WS2, WCl4 Two d-electrons; frequently seen in layered dichalcogenides (WS2, WSe2) used in 2D materials research.
+3 Moderate WCl3, W2(OR)6 Forms tungsten–tungsten multiple bonds in cluster compounds. Less common than +4 or +6.
+2 Limited WBr2, [W(CO)4(PR3)2] Stabilized mainly by strong-field ligands (CO, phosphines). Rarely observed with purely ionic ligands.
0 Organometallic W(CO)6 Tungsten hexacarbonyl — classic 18-electron organometallic. W is formally zero-valent, stabilized by π-back-bonding.
−1 Rare Na2[W(CO)5] Found in carbonylate anion clusters; requires strongly reducing conditions and inert atmosphere.
−2 Very rare K2[W(CO)5]²⁻ Extreme negative state; only in carbonyl dianion clusters. Primarily of academic interest.
Why does +6 dominate?
Tungsten has the electron configuration [Xe] 4f14 5d4 6s2. Relativistic effects contract and stabilize the 6s orbital, raising the 5d levels slightly and making all six outer electrons available for bonding with strongly electronegative partners. The resulting W=O and W–F bonds are exceptionally strong, thermodynamically driving the +6 state in oxide and fluoride chemistry. In contrast, heavy Group 6 congeners like W more readily achieve +6 than lighter Cr, which more commonly stops at +3 due to weaker relativistic stabilization.
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Summary

Reference for all known oxidation states of tungsten (W, element 74), with +6 dominant, real compound examples for each state, electron configuration, and physical properties.

How it works

  1. Click a tab — Oxidation States, Compounds, Electron Config, or Physical Props — to explore each section.
  2. The Oxidation States panel lists every known state from −2 to +6 with a stability rating and notes.
  3. The Compounds panel provides a table of representative tungsten compounds, their formulas, and the W oxidation state.
  4. The Electron Config panel shows the orbital filling diagram for W and W⁶⁺, plus the ionization energy context.
  5. The Physical Props panel gives atomic and material data including the record-setting melting point.
  6. Click any monospace table cell to copy its value to clipboard.

Use cases

  • Chemistry students studying d-block transition metal oxidation states and trends.
  • Teachers preparing lessons on Group 6 periodic trends (Cr, Mo, W).
  • Materials scientists and engineers working with tungsten carbide, tungsten electrodes, or WO3 thin films.
  • Researchers in electrochromic devices or catalysis who need oxidation state context for tungsten bronzes.
  • Anyone preparing for inorganic chemistry exams covering Period 6 metals.

Frequently Asked Questions

Last updated: 2026-07-23 · Reviewed by Nham Vu