Experimental evidence of mesoscopic order in the apparently amorphous glacial phase of the fragile glass former triphenylphosphite

We present a neutron scattering study over a wide range of wave vectors of the structure of the fragile glass former triphenylphosphite, with an emphasis on the recently discovered, apparently amorphous, glacial phase. Direct evidence is given by small-angle scattering data that the glacial phase has a structural organization on a mesoscopic scale (similar to 80 Angstrom). Our analysis supports the interpretation of the glacial phase as a poorly crystallized phase with an unusually large unit cell and unusually small crystallites. Consequences for the theory of fragile glass-forming liquids are discussed.