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Physicochemical properties and structural dynamics of organic-inorganic hybrid [NH₃(CH₂)₃NH₃]ZnX₄ (X = Cl and Br) crystals.

ABSTRACT: The physical properties of the organic-inorganic hybrid crystals having the formula [NH₃(CH₂)₃NH₃]ZnX₄ (X = Cl, Br) were investigated. The phase transition temperatures (T_C; 268K for Cl and 272K for Br) of the two crystals bearing different halogen atoms in their skeletons were determined through differential scanning calorimetry. The thermodynamic properties of the two crystals were investigated through thermogravimetric analysis. The structural dynamics, particularly the role of the [NH₃(CH₂)₃NH₃] cation, were probed through ¹H and ¹³C magic-angle spinning nuclear magnetic resonance spectroscopy as a function of temperature. The ¹H and ¹³C NMR chemical shifts did not show any changes near T_C. In addition, the ¹H spin-lattice relaxation time (T_1ρ) varied with temperature, whereas the ¹³C T_1ρ values remained nearly constant at different temperatures. The T_1ρ values of the atoms in [NH₃(CH₂)₃NH₃]ZnCl₄ were higher than those in [NH₃(CH₂)₃NH₃]ZnBr₄. The observed differences in the structural dynamics obtained from the chemical shifts and T_1ρ values of the two compounds can be attributed to the differences in the bond lengths and halogen atoms. These findings can provide important insights or potential applications of these crystals.

SUBMITTER: Lim AR

PROVIDER: S-EPMC8052450 | biostudies-literature |

REPOSITORIES: biostudies-literature

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