Light-harvesting is one of the key steps in photosynthesis, but developing artificial light-harvesting systems (LHSs) with high energy transfer efficiencies has been a challenging task. Here we report fluorescent hexagonal Pt­(II) metalla­cycles as a new platform to fabricate artificial LHSs. The metalla­cycles (4 and 5) are easily accessible by coordination-driven self-assembly of a triphenyl­amine-based ditopic ligand 1 with di-platinum acceptors 2 and 3, respectively. They possess good fluorescence properties both in solution and in the solid state. Notably, the metalla­cycles show aggregation-induced emission enhancement (AIEE) characteristics in a DMSO–H2O solvent system. In the presence of the fluorescent dye Eosin Y (ESY), the emission intensities of the metalla­cycles decrease but the emission intensity of ESY increases. The absorption spectrum of ESY and the emission spectra of the metalla­cycles show a considerable overlap, suggesting the possibility of energy transfer from the metalla­cycles to ESY, with an energy transfer efficiency as high as 65% in the 4 a +ESY system.

In recent years, there have been significant efforts put forth by the materials science researchers to search for new phasechange materials especially possessing the caliber of influencing switchable phase changes i.e., from crystalcrystal and crystalamorphous. Phasechange materials of such kind have attracted a tremendous demand for the technologically important applications such as current resistive memories and thermal energy storage. In the present article, the switchable phase transitions of amorphousglassy -crystallineamorphous occurring in the samples of lithium sulfate have been systematically experimented and demonstrated at dynamic shock wave loaded conditions of various counts of shock pulses. The shocked samples have been evaluated by the powder X-ray diffraction (PXRD), Ultraviolet Visible spectroscopy (UV-Vis) and Raman spectroscopy. Shock wave induced orientational order-disorder of the SO 4 tetrahedron and the positional disorders of the lithium atoms have led to the observed switchable phase transitions with respect to the number of shock pulses.