Rb
rubidium · Rb
Rubidium is a reactive alkali metal that exhibits semiconducting electronic properties and maintains high thermodynamic stability.
About rubidium
Rubidium is a highly reactive alkali metal that exists as a thermodynamically stable phase on the convex hull. It is characterized by its distinct electronic properties, which include semiconducting behavior under specific conditions, making it a subject of significant interest in condensed matter physics.
Due to its high chemical reactivity and physical characteristics, this element is widely utilized in specialized research and industrial applications. Its extensive structural data, represented by numerous reported configurations, underscores its importance as a foundational material in atomic and molecular studies.
Key Properties
Cross-validated computational properties for rubidium, aggregated across 4 databases.
Band GapEnergy needed to move an electron from the valence band to the conduction band. Lower or zero values tend to behave more metallic; larger gaps are more insulating or semiconducting.
Energy Above HullThermodynamic distance from the most stable set of competing phases. 0 eV/atom is on the convex hull; small positive values may still be experimentally accessible.
StabilityA plain-language summary of the best reported energy-above-hull result. It reflects whether the lowest-energy structure is on, near, or far from the stability hull.
StructuresCount of reported calculated crystal structures for this formula, including alternate polymorphs, source databases, and observed space groups.
Reported Structures
Lowest-energy structures reported for Rb, ranked by energy above hull.
| Space GroupSymmetry classification of the crystal arrangement. The number is the international space-group index. | Crystal SystemBroad lattice family, such as cubic, tetragonal, monoclinic, or triclinic, derived from unit-cell symmetry. | Band Gap (eV)Electronic gap calculated for this specific reported structure, measured in electronvolts. | E above hull (eV/atom)Thermodynamic distance from the convex hull for this structure, normalized per atom. Lower is generally more stable. | E/atom (eV)Computed total energy normalized per atom. Use energy above hull, not this value alone, when comparing stability. | Density (g/cm³)Mass per relaxed crystal volume, reported in grams per cubic centimeter. |
|---|---|---|---|---|---|
| C2/c (No. 15) | monoclinic | 0.00 | 0.0000 | -0.981 | 1.57 |
| Ibam (No. 72) | orthorhombic | 0.00 | 0.0001 | -13.931 | 1.50 |
| P63/mmc (No. 194) | hexagonal | 0.00 | 0.0022 | -0.978 | 1.50 |
| Imm2 (No. 44) | orthorhombic | 0.00 | 0.0047 | -13.926 | 1.48 |
| I4/mmm (No. 139) | tetragonal | 0.00 | 0.0074 | -0.973 | 1.49 |
| P4132 (No. 213) | cubic | 0.00 | 0.0075 | -0.973 | 1.46 |
| Ibam (No. 72) | orthorhombic | 0.00 | 0.0087 | -13.922 | 1.48 |
| Im-3m (No. 229) | cubic | 0.00 | 0.0092 | -0.971 | 1.50 |
| P63/mmc (No. 194) | hexagonal | 0.00 | 0.0100 | -0.971 | 1.50 |
| Cmcm (No. 63) | orthorhombic | 0.00 | 0.0118 | -0.969 | 1.49 |
| C2/c (No. 15) | monoclinic | 0.00 | 0.0144 | -13.916 | 1.49 |
| Fm-3m (No. 225) | cubic | 0.00 | 0.0153 | -0.965 | 1.47 |
Applications
Where rubidium is used.
Frequently Asked Questions
Common questions about rubidium, answered from cross-validated data.
What is Rb?
Rubidium is a reactive alkali metal that exhibits semiconducting electronic properties and maintains high thermodynamic stability.
What is Rb used for?
What is the band gap of Rb?
Is Rb a metal, semiconductor, or insulator?
Is Rb thermodynamically stable?
What is the crystal structure of Rb?
What is the density of Rb?
How many polymorphs of Rb are known?
What elements does Rb contain?
Where does the data for Rb come from?
How It Compares
As a singular elemental metal, rubidium occupies a unique position in materials science, serving as a primary reference point for understanding the behavior of heavy alkali metals in various structural and electronic environments.
Data sources & attribution
- materials_project — Data from the Materials Project. Cite: Jain et al., APL Materials 1, 011002 (2013).
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