Metastable Metal Hydrides for Hydrogen Storage

<table>Crystal structures of alpha aluminum hydride (<i>α</i>-AlH<sub>3</sub>), showing AlH<sub>6</sub> octahedra, and magnesium alanate (Mg(AlH<sub>4</sub>)<sub>2</sub>) showing <svg height="16.3125" id="M34" style="vertical-align:-3.27605pt" version="1.1" viewbox="0 0 54.912498 16.3125" width="54.912498" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,12.162)"><path d="M290 -163h-170v866h170v-28q-79 -7 -94 -19.5t-15 -72.5v-627q0 -59 14.5 -71.5t94.5 -19.5v-28z" id="x5B"></path></g><g transform="matrix(.017,-0,0,-.017,5.927,12.162)"><path d="M673 0h-245v28q47 6 58 16t1 39l-55 154h-213q-31 -87 -36 -129q-16 -47 -5 -61t68 -19v-28h-226v28q50 7 68.5 23.5t43.5 80.5l214 524l24 9l193 -536q23 -63 41.5 -79.5t68.5 -21.5v-28zM418 280l-81 255h-2q-74 -197 -101 -255h184z" id="x41"></path></g><g transform="matrix(.017,-0,0,-.017,17.707,12.162)"><path d="M238 0h-223v26q48 5 60 17t12 61v473q0 50 -10.5 60.5t-58.5 15.5v24q73 8 148 35v-608q0 -49 11.5 -61t60.5 -17v-26z" id="x6C"></path></g><g transform="matrix(.017,-0,0,-.017,22.008,12.162)"><path d="M729 650v-28q-62 -5 -76 -19.5t-14 -75.5v-404q0 -62 13.5 -76t75.5 -19v-28h-268v28q65 5 79.5 19t14.5 76v199h-341v-199q0 -62 14 -76t76 -19v-28h-263v28q61 5 74.5 19t13.5 76v404q0 62 -14 76t-76 19v28h259v-28q-58 -5 -71 -19t-13 -76v-162h341v162
q0 61 -13.5 75.5t-72.5 19.5v28h261z" id="x48"></path></g>
<g transform="matrix(.012,-0,0,-.012,35.05,16.25)"><path d="M456 178h-96v-72q0 -51 12.5 -62.5t72.5 -16.5v-27h-256v27q65 5 78 17t13 62v72h-260v28q182 271 300 426h40v-407h96v-47zM280 225v295h-2q-107 -148 -196 -295h198z" id="x34"></path></g>
<g transform="matrix(.017,-0,0,-.017,41.375,12.162)"><path d="M226 -163h-170v27q79 7 94 20t15 73v627q0 59 -15 72t-94 20v27h170v-866z" id="x5D"></path></g>
<g transform="matrix(.012,-0,0,-.012,47.25,4)"><path d="M535 230h-483v50h483v-50z" id="x2212"></path></g>
</svg>  tetrahedra and Mg<sup>+</sup> cation (yellow) viewed along the <svg height="14.85" id="M35" style="vertical-align:-2.22495pt" version="1.1" viewbox="0 0 36.337502 14.85" width="36.337502" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,12.012)"><path d="M290 -163h-170v866h170v-28q-79 -7 -94 -19.5t-15 -72.5v-627q0 -59 14.5 -71.5t94.5 -19.5v-28z" id="x5B"></path></g><g transform="matrix(.017,-0,0,-.017,5.927,12.012)"><path d="M241 635q53 0 94 -28.5t63.5 -76t33.5 -102.5t11 -116q0 -58 -11 -112.5t-34 -103.5t-63.5 -78.5t-94.5 -29.5t-95 28t-64.5 75t-34.5 102.5t-11 118.5q0 58 11.5 112.5t34.5 103t64.5 78t95.5 29.5zM238 602q-32 0 -55.5 -25t-35.5 -68t-17.5 -91t-5.5 -105
q0 -76 10 -138.5t37 -107.5t69 -45q32 0 55.5 25t35.5 68.5t17.5 91.5t5.5 105t-5.5 105.5t-18 92t-36 68t-56.5 24.5z" id="x30"></path></g><g transform="matrix(.017,-0,0,-.017,14.086,12.012)"><path d="M241 635q53 0 94 -28.5t63.5 -76t33.5 -102.5t11 -116q0 -58 -11 -112.5t-34 -103.5t-63.5 -78.5t-94.5 -29.5t-95 28t-64.5 75t-34.5 102.5t-11 118.5q0 58 11.5 112.5t34.5 103t64.5 78t95.5 29.5zM238 602q-32 0 -55.5 -25t-35.5 -68t-17.5 -91t-5.5 -105
q0 -76 10 -138.5t37 -107.5t69 -45q32 0 55.5 25t35.5 68.5t17.5 91.5t5.5 105t-5.5 105.5t-18 92t-36 68t-56.5 24.5z" id="x30"></path></g><g transform="matrix(.017,-0,0,-.017,22.246,12.012)"><path d="M384 0h-275v27q67 5 81.5 18.5t14.5 68.5v385q0 38 -7.5 47.5t-40.5 10.5l-48 2v24q85 15 178 52v-521q0 -55 14.5 -68.5t82.5 -18.5v-27z" id="x31"></path></g><g transform="matrix(.017,-0,0,-.017,30.405,12.012)"><path d="M226 -163h-170v27q79 7 94 20t15 73v627q0 59 -15 72t-94 20v27h170v-866z" id="x5D"></path></g>
</svg> direction [<a href="/journals/isrn/2012/863025/#B46">18</a>, <a href="/journals/isrn/2012/863025/#B67">77</a>].</table>

International Scholarly Research Notices

Metastable Metal Hydrides for Hydrogen Storage

Figure 2