[MnCl3(H2O)3]- to [MnCl6]4-: The effect of inorganic polyhedron transformation on luminescence characteristics

Organic-inorganic hybrid halides (OIHs) have attracted widespread attention because of their exceptional optoelectronic properties. In particular, Mn 2+ -based hybrid halides show intense green or red emission, which benefit from distinct d-d optical transition in Mn 2+ . This work deals with the dual-emission in two novel hybrid single-crystals (N-AEP)[MnCl 3 (H 2 O) 3 ] 2 ·Cl ( 1 ) and [(N-AEP) 2 MnCl 6 ]·2Cl ( 2 ) (N-AEP 3+  = C 6 H 18 N 3 3+ ). Luminescence properties studies indicate that the low-energy emission is assigned to the Mn 2+ -based octahedron , while the high-energy emission ascribes to the organic cation [N-AEP] 3+ . Inorganic polyhedron transformation ([MnCl 3 (H 2 O) 3 ] - to [MnCl 6 ] 4- ) increased the luminescent intensity, which benefited from the weaker nonradiative transition in [MnCl 6 ] 4- octahedron. Significantly, by finely adjusting the excitation wavelength, complex 2 showed tunable emission properties, realizing the transition from “warm” white light (0.40, 0.33) to “cold” white light (0.28, 0.28). This paper offers a new example on the effective design of dual-emission materials.