On the number of amorphous phases in n-butanol

We report on the discovery of a new solid, presumably amorphous n-butanol at ambient pressure. According to the literature data the melting point Tm of n-butanol is 183 K and the glass transition temperature Tg is 118 K. If kept isothermally at a fixed temperature between 130 and 160 K, the supercooled liquid n-butanol undergoes remarkable phase transformations to a solid phase. The new phase converts to liquid at a temperature of about 170 K. It is presumably amorphous because foreign substances dissolved in liquid n-butanol keep the same state in this new phase of butanol. The kinetics of free radical oxidation by dissolved oxygen in both solid amorphous phases is investigated in detail.