Hafnium (Hf): Electron Configuration, Properties and Uses
Hafnium (Hf): Electron Configuration, Properties and Uses
Electron configuration [Xe] 6s2 4f14 5d2 · group 4 · period 6 · Ar 178.49
Hafnium data
- Atomic number
- 72
- Relative atomic mass
- 178.49
- Group
- 4
- Period
- 6
- Block
- d
- Category
- Transition metal
- Electron configuration
- [Xe] 6s2 4f14 5d2
- Full configuration
- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d2
- Electrons per shell
- 2, 8, 18, 32, 10, 2 (K L M N O P)
- Valence electrons
- 4
- Electronegativity (Pauling)
- 1.3
- First ionisation energy
- 6.825 eV
- Atomic radius (van der Waals)
- 212 pm
- State at room temperature
- Solid
- Melting point
- 2233 °C
- Boiling point
- 4603 °C
- Density
- 13.3 g/cm³
- Common oxidation states
- +4
- Discovered
- 1923
Source: PubChem (NIH, accessed 13 Nov 2026); atomic mass: IUPAC standard atomic weight.
Electron shell diagram
K 2 · L 8 · M 18 · N 32 · O 10 · P 2
Orbital diagram (outer electrons)
About hafnium
Hafnium is a chemical element with the symbol Hf and atomic number 72. It is a transition metal in group 4, period 6, d-block. Hafnium was first discovered in 1923. Hafnium is a solid at room temperature, melting at 2233 °C and boiling at 4603 °C.
Hafnium electron configuration
The electron configuration of hafnium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d2, or in short [Xe] 6s2 4f14 5d2. Its electrons occupy 6 shells: K = 2, L = 8, M = 18, N = 32, O = 10, P = 2. For transition metals, valence electrons are counted from the 6s and 5d subshells: 2 + 2 = 4, matching group 4. When it forms cations, electrons leave the outermost subshell first: Hf4+ = [Xe] 4f14.
Filling order: 1s2(2) → 2s2(4) → 2p6(10) → 3s2(12) → 3p6(18) → 4s2(20) → 3d10(30) → 4p6(36) → 5s2(38) → 4d10(48) → 5p6(54) → 6s2(56) → 4f14(70) → 5d2(72)
Uses of hafnium
The main uses of hafnium include nuclear reactor control rods and the high-k dielectric (HfO2) in modern chip transistors.
Safety
As a solid metal, hafnium is not especially hazardous. Fine powder can burn, and its compounds should be handled according to their SDS. Always read the safety data sheet (SDS) before working with a chemical.
Other elements in group 4
Frequently asked questions
What is the electron configuration of hafnium?
The electron configuration of hafnium (Hf, atomic number 72) is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d2, or [Xe] 6s2 4f14 5d2 in short. By shell: 2, 8, 18, 32, 10, 2.
How many valence electrons does hafnium have?
Hafnium has 4 valence electrons.
Which group and period is hafnium in?
Hafnium is in group 4, period 6, d-block.
What is the atomic mass of hafnium?
The relative atomic mass of hafnium is 178.49. Use it to calculate molar mass with the molar mass calculator.
Prepare solutions with analytical-grade reagents
AMI Scientific is one of the official TCI distributors in Indonesia. Reagents with lot CoA & SDS, formal quotations and tax invoices for universities and laboratories.
Other formulas & calculators: molarity, mole, molality, normality, dilution, titration, pH, buffer, molar mass, ppm, mole fraction, mass percent, periodic table, chemical MSDS.
