NaI

ceramic
· NaI

Sodium iodide (NaI) is an ionic ceramic compound formed from sodium and iodine, belonging to the halide salt family with a rock-salt crystal structure. It is primarily used as a scintillation detector material in radiation detection systems, where its high stopping power for gamma rays and excellent light output make it the standard choice for medical imaging (PET/SPECT scanners), nuclear spectroscopy, and radiation monitoring equipment. NaI is valued for its superior energy resolution and detection efficiency compared to alternatives like plastic scintillators, though it requires careful handling due to hygroscopic properties and is often used in thallium-doped form (NaI:Tl) to enhance luminescence efficiency.

gamma ray detectionmedical imaging systemsnuclear spectroscopyradiation monitoringscintillation detectorssecurity screening

Compliance & Regulations

?Conflict Free?RoHS?REACH?TSCA?Prop 65
PropertyValueUnitConditionsSource
Bulk Modulus(K)3 entries
2,285.1
ksi
2,285.1
ksi
2,600.5
ksi
Elastic Compliance Tensor(Sij)
Matrix (redacted)
1/GPa
Elastic Anisotropy(AU)
0.2333
-
Elastic Stiffness Tensor(Cij)
Matrix (redacted)
ksi
Poisson's Ratio(ν)2 entries
0.2722
-
0.2600
-
Shear Modulus(G)3 entries
1,227.8
ksi
1,227.8
ksi
1,578
ksi
N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form / heat treatment / basis.
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Density(ρ)
0.1353
lb/in³
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Band Gap(Eg)2 entries
5.800
eV
3.851
eV
Dielectric Constant (Relative Permittivity)(εr)3 entries
8.360
-
7.087
-
5.424
range 3.488–7.359median of 2 measurements
-
Electronic Dielectric Tensor(ε∞)
Matrix (redacted)
-
Total Dielectric Tensor(ε)
Matrix (redacted)
-
Magnetic Moment(μB)
0.000
µB
Piezoelectric Modulus(eij)
0.000
C/m²
Seebeck Coefficient(S)
-77.72
µV/K
N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form / heat treatment / basis.
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Energy Above Hull(ΔEhull)
0.00900
eV/atom
Formation Energy(ΔHf)2 entries
-1.492
eV/atom
-1.358
eV/atom
N entriesMultiple entries per property — large groups are collapsed; click a summary row to expand. Use filters above to narrow by form / heat treatment / basis.
Verified Unverified Low confidence (<80%) Link to source

Regulatory Screening

Environmental

RoHS, REACH, and Prop 65 statuses are validated against official substance lists (ECHA SVHC Candidate List, OEHHA Prop 65, RoHS Annex II). Other regulations are estimated from composition and material classification. All screening is a starting point for due diligence — always verify with your supplier before making compliance decisions.
NaI — Properties & Data | MatWorld