Chromium nitride

Chromium nitride
IUPAC name Chromium nitride
Other names Chromium(III) nitride
Identifiers
CAS number	24094-93-7 Y
ChemSpider	81581 Y
Jmol-3D images	Image 1
SMILES [Cr]#N
InChI InChI=1S/Cr.N Y Key: CXOWYMLTGOFURZ-UHFFFAOYSA-N Y InChI=1/Cr.N/rCrN/c1-2 Key: CXOWYMLTGOFURZ-NIYUYJRQAK
Properties
Molecular formula	CrN
Molar mass	66.003 g/mol
Appearance	Black powder
Density	5.9 g/cm3 [1]
Melting point	1770 ˚C (decomp.)[2]
Solubility in water	Insoluble[3]
Thermochemistry
Std enthalpy of formation ΔfHo298	−117.15 kJ/mol [4]
Standard molar entropy So298	37.75 J K−1 mol−1 [4]
Hazards
EU Index	Not listed
Flash point	Non-flammable
Related compounds
Related compounds	Dichromium nitride
Y nitride (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Chromium nitride is a chemical compound of chromium and nitrogen with the formula CrN. It is very hard, and is extremely resistant to corrosion. It is an interstitial compound, with nitrogen atoms occupying the octahedral holes in the chromium lattice:^[2] as such, it is not strictly a chromium(III) compound nor does it contain nitride ions (N³⁻). Chromium forms a second interstitial nitride, dichromium nitride, Cr₂N.

Synthesis

Chromium(III) nitride can be prepared by direct combination of chromium and nitrogen at 800 °C:

2 Cr + N₂ → 2 CrN

It can also synthesize by Physical Vapour Deposition technique such as Cathodic arc deposition.

Applications

CrN is used as a coating material for corrosion resistance and in metal forming and plastic moulding applications^[5]. CrN is often used on medical implants and tools. CrN is also a valuable component in advanced multicomponent coating systems, such as CrAlN, for hard, wear-resistant applications on cutting tools^[6].

Magnetism

The fundamental materials physics of CrN, giving rise to its favorable properties, has been debated recently in high-profile scientific journals such as Nature Materials^{[7] [8]}. In particular, the importance of magnetism in both the low temperature and the high temperature phases has been demonstrated by means of quantum mechanical calculations of the electronic structure of the compound^{[9] [10] [11]}.

References

1. ^ Chromium(III) nitride at webelements.com
2. ^ ^{a b} Greenwood, Norman N.; Earnshaw, A. (1984). Chemistry of the Elements. Oxford: Pergamon. p. 480. ISBN 0-08-022057-6. 
3. ^ http://www.alfa-chemcat.com/daten_msds/D/12149_-_D.pdf
4. ^ ^{a b} NIST Chemistry Webbook
5. ^ J. Vetter, Surf. Coat. Technol. 76, 719 (2005)
6. ^ A. E. Reiter, V. H. Derflinger, B. Hanselmann, T. Bachmann, and B. Sartory, Surf. Coat. Technol. 200, 2114 (2005).
7. ^ F. Rivadulla et al., Nature Mater. 8, 947 (2009)
8. ^ B. Alling, T. Marten, and I. A. Abrikosov, Nature Materials 9, 283, (2010)
9. ^ A. Filippetti and N. A. Hill, Phys. Rev. Lett. 85, 5166 (2000).
10. ^ A. Herwadkar and W. R. L. Lambrecht, Phys. Rev. B 79, 035125 (2009)
11. ^ B. Alling, T. Marten, and I. A. Abrikosov, Physical Review B, 82, 184430 (2010)