Metal ion-dependent structural phase transition and impact of the Jahn–Teller effect in two organic–inorganic hybrid compounds

Two new compounds, (H 2 dabco)[M(H 2 O) 6 ][SiF 6 ] 2 (dabco = 1,4-diazabicyclo [2.2.2] octane, M = Mn 2+ & Cu 2+ ), exhibit metal ion-dependent structural phase transitions, large dielectric response, SHG (M = Mn 2+ ) and ferroelasticity (M = Cu 2+ ).