Preparation and Characterization of Two Bismuth(III) Iodide Inorganic/Organic Hybrid Solids

Abstract

Two new organic/bismuth(III) iodide hybrids have been synthesized by a solution process, and their crystal structures were determined by an x-ray diffraction method. The first one, (EMP)3(Bi2I9) (EMP+ = N-ethyl-4-methyl-pyridinium) (1), crystallizes in the monoclinic system, space group P21/c, with M r = 3838.20, a = 19.945(4), b = 12.636(3), c = 20.327(4) Å, β = 118.82(3)°, V = 4488.4(16) Å3, Z = 2, D c = 2.840 g/cm3, F(000) = 3358, μ(MoKα) = 14.039 mm−1, the final R = 0.0678, and wR = 0.1676 for 7272 observed reflections with I > 2σ(I). The second, [(Phendione)BiI4]·(Phendione-H)·C2H5OH (Phendione = 1,10-phenathroline-5,6-dione) (2), belongs to the monoclinic system, space group C2/c, with M r = 1183.02, a = 37.254(8), b = 8.1776(16), c = 22.318(5) Å, β = 111.38(3)°, V = 6331(2) Å3, Z = 8, D c = 2.842 g/cm3, F(000) = 4296, μ(MoKα) = 9.511 mm−1, the final R = 0.0526, and wR = 0.1050 for 6555 observed reflections with I > 2σ(I). Compound 1 contains halobismuthate dimers, and it is noteworthy that the dimers and its organic countercations connect with each other by C–H···I hydrogen bonds to form a layered structure. Compound 2 is composed of [(Phendione)BiI4]− anions and Phendione-H+ cations, and hydrogen bonds contribute to give a one-dimensional (1-D) chain. The optical absorption spectra of 1 and 2 reveal the appearance of sharp optical gaps of 2.17 and 1.93 eV, respectively.