Crystal structures, hhirshfeld surfaces analysis, Infrared and Raman studies of organic-inorganic hybrid perovskite salts NH3(CH2)nNH3MnCl4 (n = 5, 6)

Abstract

Layered 2D organic-inorganic hybrid perovskite (OIHs) of the diammonium series, 1,5 di-aminepentane tetrachloro manganate NH3(CH2)5NH3MnCl4 denoted C5MnCl and 1,6 di-aminhexane tetrachloro manganate NH3(CH2)6NH3MnCl4 (C6MnCl) were prepared by slow evaporation method, and structurally characterized by single crystal X-ray diffraction analysis. The C5MnCl hybrid crystallized in the orthorhombic non-centrosymmetric space group I212121 (Z ​= ​4) with parameters: a ​= ​7.1742 (3) Å, b ​= ​7.3817 (3) Å, c ​= ​23.9650 (10) Å, V ​= ​1269.13 ​Å3. While the C6MnCl crystallized in the centrosymmetric monoclinic system with P21/c (Z ​= ​4) space group, and unit cell dimensions: a ​= ​13.3738 (6) Å, b ​= ​7.3227 (3) Å, c ​= ​7.1886 (3) Å, β ​= ​93.673 (4)°. The both hybrid structures consist of organic dications ​+ ​NH3(CH2)nNH3+ (n ​= ​5, 6) extended in a zigzag structure while inorganic dianion manganate was coordinated by six Cl ions in distorted octahedra MnCl62− sharing two bridging chlorine atoms. The organic and inorganic layers were connected each other through N–H ….Cl hydrogen bonds to build cation-anion-cation structural cohesion. The Hirshfeld surface analyses are performed to compare the importance of hydrogen bonding contacts in the two hybrid compounds, where the H⋯Cl/Cl⋯H intercontacts are more important in C5MnCl rather in C6MnCl. Theoretical vibrational modes analyses are developed considering the structural data obtained on ​+ ​NH3(CH2)nNH3+ cations and MnCl42− anions to study the characteristic bands observed at room temperature in Infrared (400-4000 ​cm−1) and Raman (50-500 ​cm−1) spectra of the C6MnCl and C5MnCl compounds.