Sublattice magic?!-Phase transitions in superionics

296-304Mobile-ion sublattice formation and instability lead to interesting superionic phase transitions crucial to realization of Ag+ and Li+ superionic conductors. Superionicity is focused as ‘sublattice magic’ underscoring the mystery that is fundamentally interesting for further progress. AgCuSe, Ag3CuS2 and Li3DyBr6 are typical of an emerging breed of new superionics with as interesting physics as AgI and its ternaries. Mechanochemical reaction of Ag,Cu and I has given a facile new fabrication technology to investigate phase transitions by novel techniques such as EPR and electronic conductivity. HTXRD of AgI-CuI system has helped to investigate the phase diagram which has shown features including extended stability of γ-AgI and suppression of diffuse scattering in α-AgI. LiFePO4 made from a novel non-aqueous sol-gel technology is Fe3+ and enable para-antiferromagnetic phase transition to be investigated. Plasmon-exciton transition-a novel quasi-particle transition in iodized Ag thin films has promise for Surface Plasmon Resonance (SPR) sensing and iodine detection