Np

metal

· JVASP-25118· Np

Neptunium (Np) is a synthetic actinide metal produced primarily as a byproduct of nuclear reactor operation and plutonium production. It is highly dense, radioactive, and used almost exclusively in nuclear fuel research, advanced reactor development, and specialized scientific applications where its nuclear properties are exploited rather than its mechanical characteristics.

nuclear fuel researchreactor physics studiesactinide metallurgyweapons-grade material productionscientific isotope applicationsnuclear nonproliferation studies

Compliance & Regulations

?EAR?Conflict Free?RoHS?REACH?TSCA?Prop 65

Units:

si imperial

Property	Value	Unit	Conditions
Bulk Modulus(K)	26,508.5	ksi	DFT · OptB88vdW
Poisson's Ratio(ν)	0.4600	-	DFT · OptB88vdW
Shear Modulus(G)	3,190.8	ksi	DFT · OptB88vdW

Verified Unverified Low confidence (<80%) Link to source

Property	Value	Unit	Conditions	Source
Density(ρ)	0.7883	lb/in³	DFT · OptB88vdW

Verified Unverified Low confidence (<80%) Link to source

Filter by

Method

Carrier

Property	Value	Unit	Conditions
Band Gap(Eg)2 entries	0.000	eV	DFT · OptB88vdW
↳	0.000	eV	DFT · TBmBJ
Magnetic Moment(μB)	0.00100	µB	DFT · OptB88vdW
Thermoelectric Power Factor(PF)2 entries	0.000574	W/(m·K²)	DFT · OptB88vdW · n-type · 1e20 cm⁻³ · 327°C
↳	0.000568	W/(m·K²)	DFT · OptB88vdW · p-type · 1e20 cm⁻³ · 327°C
Seebeck Coefficient(S)2 entries	-3.353	μV/K	DFT · OptB88vdW · n-type · 1e20 cm⁻³ · 327°C
↳	-3.350	μV/K	DFT · OptB88vdW · p-type · 1e20 cm⁻³ · 327°C

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, or test environment.

Verified Unverified Low confidence (<80%) Link to source

Property	Value	Unit	Conditions	Source
Energy Above Hull(ΔEhull)	0.000	eV/atom	DFT · OptB88vdW
Formation Energy(ΔHf)	0.000	eV/atom	DFT · OptB88vdW

Verified Unverified Low confidence (<80%) Link to source

Reference data from cited sources. Not verified or certified by MatWorld Inc. Verify against the source before use in design. Terms: engineering data

Regulatory Screening

Environmental

Export Control

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.

Np — Properties & Data | MatWorld

Np

Mechanical Properties

Physical Properties

Electrical Properties

Other Properties

Regulatory Screening

Environmental

Export Control