Lanthanum phosphide

Lanthanum phosphide
Names
	Other names Phosphanylidynelanthanum
Identifiers
CAS Number	25275-74-5;
3D model (JSmol)	Interactive image;
ECHA InfoCard	100.042.515
EC Number	246-782-9;
PubChem CID	91371;
CompTox Dashboard (EPA)	DTXSID401311967 ;
	InChI InChI=1S/La.P Key: GZHCNRONBGZNAH-UHFFFAOYSA-N;
	SMILES P#[La];
Properties
Chemical formula	LaP
Molar mass	169.88
Appearance	Black crystals
Density	5.2 g/cm3
Solubility in water	Reacts with water
Structure
Crystal structure	Rock salt structure
Space group	Fm3m
Lattice constant	a = 0.6025 nm
Formula units (Z)	4
Coordination geometry	Octahedral at La3+, Octahedral at P3-
Related compounds
Other anions	Lanthanum nitride; Lanthanum arsenide; Lanthanum bismuthide
Other cations	Scandium phosphide; Yttrium phosphide; Cerium phosphide
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Lanthanum phosphide is an inorganic compound of lanthanum and phosphorus with the chemical formula LaP.

Synthesis

Lanthanum phosphide can be made by heating lanthanum metal with excess phosphorus in a vacuum:^[2]

4 La + P₄ → 4 LaP

Physical properties

Lanthanum phosphide forms black crystals of a cubic system, space group Fm3m, cell parameters a = 0.6025 nm, with number of formulas per unit cell Z = 4.^[1]

The crystals are very unstable and decompose in the open air.

Electronic properties

Lanthanum phosphide is an example of a strongly correlated material,^[3] complicating theoretical prediction of its properties.

According to HSE06 calculations, lanthanum phosphide has been theoretically predicted to have an indirect band gap of 0.25 eV along the Γ-X direction.^[4] According to HSE06 calculations with spin-orbit coupling, the band gap is predicted to be a direct gap of 0.72 eV at the X point.^[5] Using EVGGA, the compound is predicted to have a band gap of 0.56 eV along the Γ-X direction.^[6] FP-LAPW has predicted an indirect gap of 0.33 eV along the Γ-X direction.^[3]

Chemical properties

Lanthanum phosphide reacts with water, releasing highly toxic phosphine gas:

LaP + 3H₂O → La(OH)₃ + PH₃

Uses

Lanthanum phosphide compound is a semiconductor used in high power, high frequency applications, and in laser diodes.^[7]^[8]

Lanthanum polyphosphide

In addition to the simple phosphide, LaP, lanthanum and phosphorus can also form phosphorus-rich compounds such as LaP₂^[9] LaP₅^[10] and LaP₇.^[11]

References

^ ^a ^b Standard X-ray Diffraction Powder Patterns (PDF). U.S. Department of Commerce, National Bureau of Standards. 1967-08-31. p. 69. Retrieved 2023-11-04.
^ Samsonov, G.V.; Endrzheevskaya, S.N. (September 1963). "Production and Some Properties of Lanthanum Phosphide". Journal of General Chemistry of the USSR (English Translation). 33 (9). Consultants Bureau: 2729. Google books Journal index
^ ^a ^b Shoaib, M.; Murtaza, G.; Khenata, R.; Farooq, M.; Ali, Roshan (2013). "Structural, elastic, electronic and chemical bonding properties of AB (A=Sc,Y,La;B=N,P,As,Sb,Bi) from first principles". Computational Materials Science. 79. Elsevier BV: 239–246. doi:10.1016/j.commatsci.2013.06.015. ISSN 0927-0256.
^ Yan, X. Z.; Chen, Y. M.; Kuang, X. Y.; Xiang, S. K. (2014-08-26). "Theoretical investigation of La monopnictides: Electronic properties and pressure-induced phase transition". Journal of Applied Physics. 116 (8). AIP Publishing: 083707. Bibcode:2014JAP...116h3707Y. doi:10.1063/1.4893645. ISSN 0021-8979.
^ Zhou, Yu; Tao, Wang-Li; Zeng, Zhao-Yi; Chen, Xiang-Rong; Chen, Qi-Feng (2019-01-28). "Thermoelectric properties of topological insulator lanthanum phosphide via first-principles study". Journal of Applied Physics. 125 (4). AIP Publishing: 045107. Bibcode:2019JAP...125d5107Z. doi:10.1063/1.5043170. ISSN 0021-8979.
^ Charifi, Z.; Reshak, Ali Hussain; Baaziz, H. (2008). "Phase transition of LaX (X = P, As, Sb and Bi) at high pressure: Theoretical investigation of the structural and electronic properties". Solid State Communications. 148 (3–4). Elsevier BV: 139–144. Bibcode:2008SSCom.148..139C. doi:10.1016/j.ssc.2008.07.038. ISSN 0038-1098.
^ Lewis, Robert A. (30 March 2016). Hawley's Condensed Chemical Dictionary. John Wiley & Sons. ISBN 978-1-119-19372-2. Retrieved 21 December 2021.
^ O'Bannon, Loran (6 December 2012). Dictionary of Ceramic Science and Engineering. Springer Science & Business Media. p. 151. ISBN 978-1-4613-2655-7. Retrieved 21 December 2021.
^ v. Schnering, H. G.; Wichelhaus, W.; Nahrup, M. Schulze (1975). "Zur Chemie und Strukturchemie der Phosphide und Polyphosphide. XI. Lanthandiphosphid LaP₂; Darstellung, Struktur und Eigenschaften". Zeitschrift für anorganische und allgemeine Chemie. 412 (3). Wiley: 193–201. doi:10.1002/zaac.19754120302. ISSN 0044-2313.
^ Wichelhaus, W.; Schnering, H. (1976). "Zur Chemie und Strukturchemie der Phosphide und Polyphosphide. 12. Die Pentaphosphide des Lanthans und Neodyms, LaP₅ und NdP₅". Zeitschrift für Anorganische und Allgemeine Chemie. 419: 77–86. doi:10.1002/ZAAC.19764190113. S2CID 97289383.
^ Raghavan, V. (2004). "Fe-La-P (iron-lanthanum-phosphorus)". Journal of Phase Equilibria and Diffusion. 25 (2). Springer Science and Business Media LLC: 172–173. doi:10.1007/s11669-004-0019-7. ISSN 1547-7037.