SeI2

Selenium diiodide is a stable semiconducting material formed from selenium and iodine that is frequently studied for its structural and electronic characteristics.

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Crystal structure of SeI2 (tetragonal, P42/mnm (No. 136))
Ground-state structure · Materials Project
Overview

About SeI2

Selenium diiodide is a semiconducting compound composed of selenium and iodine. As a thermodynamically stable phase located on the convex hull, it represents a well-defined chemical arrangement that maintains structural integrity under standard conditions.

With extensive data available across multiple structural databases, this compound serves as a significant subject for researchers investigating chalcogen-halide interactions. Its electronic character suggests potential utility in specialized electronic or optoelectronic applications where specific semiconductor properties are required.

At a glance

Key Properties

Cross-validated computational properties for SeI2, aggregated across 3 databases.

Band Gap

0.91 eV
Range across DFT structures

Energy Above Hull

0.000 eV/atom
Best (lowest) across sources

Stability

On hull (stable)
2 DFT sources

Structures

77
3 databases, 18 space groups
Crystallography

Reported Structures

Lowest-energy structures reported for SeI2, ranked by energy above hull.

Space GroupCrystal SystemBand Gap (eV)E above hull (eV/atom)E/atom (eV)Density (g/cm³)
P42/mnm (No. 136)tetragonal0.910.0000-2.3674.11
Pmm2 (No. 25)Orthorhombic3.92
P-1 (No. 2)Triclinic4.80
P1 (No. 1)Triclinic7.08
P1 (No. 1)Triclinic4.82
P1 (No. 1)Triclinic5.30
C2/m (No. 12)Monoclinic6.23
C2/m (No. 12)Monoclinic4.65
C2/m (No. 12)Monoclinic4.93
P1 (No. 1)Triclinic5.87
P1 (No. 1)Triclinic3.13
P1 (No. 1)Triclinic3.40
Uses

Applications

Where SeI2 is used.

Semiconductor researchMaterials science studiesChalcogen-halide chemistry
Reference

Frequently Asked Questions

Common questions about SeI2, answered from cross-validated data.

What is SeI2?

Selenium diiodide is a stable semiconducting material formed from selenium and iodine that is frequently studied for its structural and electronic characteristics.

More questions
What is SeI2 used for?
SeI2 is used in semiconductor research, materials science studies, and chalcogen-halide chemistry.
What is the band gap of SeI2?
SeI2 has a DFT-computed band gap of 0.91 eV across 77 reported structures.
Is SeI2 a metal, semiconductor, or insulator?
With a band gap up to 0.91 eV it is a semiconductor.
Is SeI2 thermodynamically stable?
Yes — SeI2 sits on the convex hull (energy above hull 0 eV/atom), i.e. on hull (stable).
What is the crystal structure of SeI2?
The lowest-energy reported polymorph of SeI2 is tetragonal symmetry, space group P42/mnm (No. 136).
What is the density of SeI2?
The computed density of the ground-state structure of SeI2 is 4.11 g/cm³.
How many polymorphs of SeI2 are known?
77 structures of SeI2 are reported across 3 databases, spanning 18 distinct space groups.
What elements does SeI2 contain?
SeI2 contains I and Se (2 elements).
Where does the data for SeI2 come from?
SeI2 data is cross-referenced from materials_project, mpaloe.
Comparison

How It Compares

As a unique binary chalcogen-halide, Selenium diiodide occupies a distinct position in materials research, serving as a fundamental reference point for understanding the bonding and stability trends within selenium-iodine systems.

Data sources & attribution
  • materials_project — Data from the Materials Project. Cite: Jain et al., APL Materials 1, 011002 (2013).
  • mpaloe — Data from mpaloe.

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