Editing Lithium aluminium hydride (section)

=== Structure ===
[[File:Lithium-aluminium-hydride-unit-cell-3D-polyhedra.png|left|upright|thumb|The crystal structure of LAH; Li atoms are purple and {{chem2|AlH4}} tetrahedra are tan.]]
LAH crystallizes in the [[monoclinic]] [[space group]] ''P''2<sub>1</sub>/''c''. The [[unit cell]] has the dimensions: ''a'' = 4.82, ''b'' = 7.81, and ''c'' = 7.92 Å, α = γ = 90° and β = 112°. In the structure, {{chem2|Li+}} [[cations]] are surrounded by five {{chem2|[AlH4]−}} [[anions]], which have [[tetrahedral molecular geometry]]. The {{chem2|Li+}} cations are bonded to one [[hydrogen]] atom from each of the surrounding tetrahedral {{chem2|[AlH4]−}} anion creating a [[bipyramid]] arrangement. At high pressures (>2.2 GPa) a phase transition may occur to give β-LAH.<ref name="crystal_structure">{{cite journal |author1=Løvvik, O. M. |author2=Opalka, S. M. |author3=Brinks, H. W. |author4=Hauback, B. C. | title = Crystal Structure and Thermodynamic Stability of the Lithium Alanates LiAlH<sub>4</sub> and Li<sub>3</sub>AlH<sub>6</sub> | journal = Physical Review B | year = 2004 | volume = 69 | issue = 13 | pages = 134117 | doi = 10.1103/PhysRevB.69.134117 |bibcode=2004PhRvB..69m4117L }}</ref>
[[File:Lialh4 xrpd.svg|left|thumb|upright|[[X-ray powder diffraction]] pattern of as-received {{chem2|Li[AlH4]}}. The asterisk designates an impurity, possibly [[Lithium chloride|LiCl]].]]