Hassium (Hs)

Unknown

Hassium is a superheavy element that forms an oxide resembling that of osmium, the densest element, and with [Rn] 5f¹⁴ 6d⁶ 7s², hassium (half-life 9 seconds for Hs-277) was shown to form the volatile tetroxide HsO₄, identical in behavior to OsO₄. This confirmed relativistic effects maintain group 8 chemistry.

Key metrics

Density21g/cm³predicted

Melting point2,500Kpredicted

Boiling point4,800Kpredicted

Electronegativity1.3Paulingpredicted

Discovery

1984discovered

Discovered by: GSI Darmstadt
Reactivity profile: Very short-lived radioactive metal
Reactivity: Low
Bonding: Metallic

Electron configuration

\textcolor{#6b7280}{[Rn]}\; \textcolor{#a855f7}{5_{f}^{14}}\; \textcolor{#22c55e}{6_{d}^{6}}\; \textcolor{#ef4444}{7_{s}^{2}}

[Rn] 5f14 6d6 7s2

Wave function

\Psi_{\text{Hs}} \approx \frac{1}{\sqrt{108!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_{108}(\mathbf{r}_{108}) \right|

Probability density $|\Psi|^2$ across the Hs valence shell.

Crystal structure

Hexagonal Close-Packed

Lattice constantsa 1.00 · b 1.00 · c 1.63

Cell anglesα 90° · β 90° · γ 120°

Coordination number12

Atoms per cell2

Atomic packing factor0.74

Physical properties

Atomic radius: 134 pmpredicted
Ionization energy: 620 kJ/molpredicted
Electron affinity: 0 kJ/molpredicted
Crystal structure: Hexagonal close-packed (predicted)

Oxidation statespredicted

Acid/base

Basic

Strongly acidicStrongly basic

State at 25 °CSolid

2500 K4800 K298 K

predicted