Atomic and electronic structures of an extremely fragile liquid

Abstract

The structure of high-temperature liquids is an important topic for understanding the fragility of liquids. Here we report the structure of a high-temperature non-glass-forming oxide liquid, ZrO2, at an atomistic and electronic level. The Bhatia–Thornton number–number structure factor of ZrO2 does not show a first sharp diffraction peak. The atomic structure comprises ZrO5, ZrO6 and ZrO7 polyhedra with a significant contribution of edge sharing of oxygen in addition to corner sharing. The variety of large oxygen coordination and polyhedral connections with short Zr–O bond lifetimes, induced by the relatively large ionic radius of zirconium, disturbs the evolution of intermediate-range ordering, which leads to a reduced electronic band gap and increased delocalization in the ionic Zr–O bonding. The details of the chemical bonding explain the extremely low viscosity of the liquid and the absence of a first sharp diffraction peak, and indicate that liquid ZrO2 is an extremely fragile liquid.

Atomic-configuration modeling of ion-conducting crystalline oxide by diffraction technique and theoretical calculation

“…In fact, a combination of the DFT and RMC has been carried out actively for glasses and melts. 47), 48) I believe that this strategy will shed new light on the defect chemistry and give a breakthrough for discovering a novel ion-conducting crystal.…”

Atomistic and electronic structures of functional disordered materials revealed by a combination of quantum-beam measurements and computer simulations

“…8. (A) BhatiaThornton number-number partial structure factor S NN (Q) for l-ZrO 2 at 2800°C derived from the DFT-MD simulation (bold curve) 16) in comparison with those for l-Al 2 O 3 at 2127°C (solid curve) 17) and l-SiO 2 at 2100°C (dotted curve). 27) The momentum transfer Q was scaled by r AX (r AX is the first coordination distance between A and X in the real-space function) to eliminate the effect of the size of cations.…”

“…(B) Coordination number distribution of oxygen around the cations in l-ZrO 2 at 2800°C, 16) l-Al 2 O 3 at 2127°C, 17) and l-SiO 2 at 2100°C. 27) (C) Polyhedral connections in l-ZrO 2 at 2800°C, 16) l-Al 2 O 3 at 2127°C, 17) and l-SiO 2 at 2100°C. 27) CS, corner sharing of oxygen; ES, edge sharing of oxygen; FS, face sharing of oxygen.…”

“…27) The momentum transfer Q was scaled by r AX (r AX is the first coordination distance between A and X in the real-space function) to eliminate the effect of the size of cations. (B) Coordination number distribution of oxygen around the cations in l-ZrO 2 at 2800°C, 16) l-Al 2 O 3 at 2127°C, 17) and l-SiO 2 at 2100°C. 27) (C) Polyhedral connections in l-ZrO 2 at 2800°C, 16) l-Al 2 O 3 at 2127°C, 17) and l-SiO 2 at 2100°C.…”

“…Then the focus will be put on research on functional disordered materials, fast-phase-change materials, 7)11) binary oxide glasses 12)14) synthesized by containerless processing, 15) and high-temperature oxide melts 16), 17) at both the atomistic and electronic levels. In particular, materials that do not contain a glass former (i.e.…”