Magnesium silicide (Mg 2 Si) undergoes a transformation from a cubic (fluorite) type lattice to a hexagonal lattice at pressures above about 25 kilobars and temperatures above 900°C. There is an increase of density of about 15 percent associated with this structure change. Both the parent and product substances are semiconductors, but of different resistivities. The high pressure phase may be recovered and is indefinitely metastable at normal ambient conditions.

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Isosorbide was functionalized with furoxan for the first time to give adducts that release nitric oxide up to 7.5 times faster than the commercial vasodilator, isosorbide-5-mononitrate (Is5N). The synthesis was facilitated by MeMgCl-mediated selective acetylation of isosorbide or selective deacetylation of isosorbide-2,5-diacetate, which was rationalized in terms of a more stable 5-alkoxide magnesium salt using DFT. Isosorbide-furoxans are safer to handle than Is5N due to greater thermal stability.

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