Ice VII

Ice VII is a cubic crystalline form of ice formed by lowering water to ambient temperatures at pressures above 1.9 GPa. The hydrogen atoms' position is disordered and the hydrogen bonds form two interpenetrating lattices. It exhibits Debye relaxation. The proton-ordered form of ice VII is ice VIII.

Ordinary water ice is known as ice I_h, (in the Bridgman nomenclature). Different types of ice, from ice II to ice XIV, have been created in the laboratory at different temperatures and pressures.

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  The crystal structure of ice XII

References

• Chaplin, Martin (2007-10-26). "Ice-seven and ice-ten structures". Water Structure and Science. Retrieved 2008-01-02.