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Abstract: Benzamidinium d-glucuronate (1) crystallizes in the orthorhombic space group P212121 and exhibits a 3D network with molecules linked by moderate intermolecular hydrogen bonds (HNH…O(solvent) 2.993Å, HNH…OCO 2.894Å, HNH…O(cycle) 2.844Å, OH…NH2 2.931Å, OH…O(solvent) 2.894, 2.924 and 2.715Å (stronger)) with participation of cations, anions and solvent molecules. The IR-band assignment of carbohydrate moieties is elucidated by a comparison between the types and bond lengths of intermolecular interactions with participation of OH groups in d-glucuronate and linear polarized IR-(IR-LD) spectroscopic data. Experimental results are supported by theoretical ab initio calculations of benzamidinium cation and d-glucuronate anion. [Copyright &y& Elsevier]

A new crystalline complex of dl -serine and squaric acid (H 2 Sq) in stoichiometric ratio 1:1 ( dl -Ser·HSq) was synthesized, isolated and structurally characterized by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2 1 /n and its structure consists of a 3D supramolecular network of hydrogensquarate anions and serinium cations directed by intermolecular hydrogen bonding interactions. The 3D network is formed by hydrogen bonds with participation of C O–OH, hydrogensquarate ion and NH 3 + group, (Sq) C O…O C (OH) (2.525 Å), – NH 3 + …O C (Sq) (2.915, 2.985 and 3.016 Å), hydroxyl group CH 2 –OH…O C (Sq) (2.739 Å), O…H–N + (3.016 Å) and (C–OH A …O C (Sq) (3.242), respectively. The structural information shows a new structural motif, a non-classic α-chain of the hydrogensquarate anions with dihedral angle between neighbouring HSq − anions 43.66°. The Raman and infrared spectra of the new crystal were measured in the 4000–50 cm −1 and 4000–400 cm −1 region frequency range respectively. The assignment of bands in infrared and Raman spectra of the crystal was performed on the basis of DFT (B3LYP) calculations, X-ray structural results and by the comparison with literature data. [ABSTRACT FROM AUTHOR]

Abstract: The title compound was synthesized and characterized by single crystal X-ray diffraction and solid-state polarized IR-spectroscopy of oriented colloids in a nematic host. The compound crystallizes in the monoclinic space group P21/c and its structure consists of a 3D supramolecular network of tyrammonium cations, water and sulfate anions directed by intermolecular hydrogen bonding interactions. Two non-equivalent tyrammonium cations are observed with pseudo T and T trans configurations, respectively. The vibrational characteristics of the non-equivalent molecules are assigned using solid-state polarized IR-spectroscopy. The structural and spectroscopic data are compared with theoretical calculations at the MP2/6-31++G∗ level of theory and basis set using the tyrammonium cation heptahydrate as a model system. [Copyright &y& Elsevier]