Aluminium five-coordinated crystal

As noted above, upon depressurization the amorphous A1P04 recrystallizes. This is the point at which the percentage of four-coordinated aluminiums jumps from 2% to 59%, while the percentage of five-coordinated aluminiums decreases from 48% to 38% and that of the six-coordinated aluminium atoms decreases sharply from 38% to just 3%. The seven-coordinated species disappear altogether upon recrystallization. As the crystal is depressurized... 

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