Jahn–Teller Effect on Framework Flexibility of Hybrid Organic–Inorganic Perovskites

Abstract

Here we study the Jahn-Teller (JT) effect on framework flexibility of two analogous hybrid organic-inorganic perovskites, [C(NH)][Zn(HCOO)] (1-Zn) and [C(NH)][Cu(HCOO)] (2-Cu). Single-crystal nanoindentation measurements show that the elastic moduli and hardnesses of 1-Zn are up to ∼52.0% and ∼25.0% greater than those of the JT active 2-Cu. Temperature-dependent X-ray diffraction measurements indicate that the thermal expansion along the b-axis is switched from negative to positive by replacing Zn with Cu on the B-site. These stark distinctions in framework flexibility are primarily attributed to the ∼10.0% elongation of Cu-O bonds induced by the JT effect and associated alterations in octahedral tilting and hydrogen-bonding. Our results demonstrate the prominence of the JT effect in the emerging hybrid perovskites and highlight the possibilities of tuning materials' properties using orbital order.

Disorder–order transitions in the perovskite metal–organic frameworks [(CH3)2NH2][M(HCOO)3] at high pressure

“…60 In other studies, the framework flexibility of [C(NH 2 ) 3 ][Cu(HCOO) 3 ] has also been shown to be increased compared to its analogous zinc formate compound due to the presence of the Jahn-Teller distortion. 61 We note that as we observe the reduction in the JT distortion under pressure, multiferroic coupling arising from JT 39 would be expected to decrease upon compression or upon chemical substitutions that reduce the volume of the equivalent unit cell.…”

Electronic structures and elastic properties of a family of metal-free perovskites

“…Up to now, the electronic and elastic properties of inorganic and organic-inorganic perovskite materials have been comprehensively researched. [17][18][19][20][21][22] However, very limited information is known about the electronic structures and elastic properties of metal-free perovskite materials, 23,24 which will certainly delay their future industrialization. In this work, the electronic and elastic properties of a family of metal-free perovskites: [(C 4 N 2 H 12 )(NH 4 X 3 )ÁH 2 O] (X = Br, Cl, I), called PIP-Cl, PIP-Br and PIP-I, respectively, have been systematically investigated, using the first principle calculations.…”

Preparation and Two-Photon Photoluminescence Properties of Organic Inorganic Hybrid Perovskites (C6H5CH2NH3)2PbBr4 and (C6H5CH2NH3)2PbI4

“…The crystal structure of a perovskite can be described with the chemical formula ABX 3 , in which A-sites are the organic ammonium cations, B-sites are the inorganic metal cations, and X-sites are the halide anions. The B-site cation is six-coordinated by the X-site anion to form [BX 6 ] octahedrons, which are corner-sharing to constitute three-dimensional frameworks [4,5]. These compounds have multiple quantum well structures with alternating organic and inorganic layers [6].…”