Synthesis, characterization, and thermal and computational investigations of the l-histidine bis(fluoride) crystal

Abstract

Nonlinear optical materials have been investigated recently due to their potential technological applications in information storage and communications. In this context, semi-organic crystals can effectively combine the desired nonlinear optical properties of amino acids with the promising mechanical and thermal properties of inorganic materials. In this work, we have synthesized and characterized a semi-organic crystal of the amino acid l-histidine and hydrofluoric acid and investigated the chemical interactions between the organic and inorganic moieties. The crystal of l-histidine bis(fluoride) has been produced by slow solvent evaporation and characterized by X-ray diffraction (XRD) crystallography and thermogravimetric and differential thermal analyses. The XRD conducted using the Rietveld method shows that the unit cell is orthorhombic with the P21212 space group and contains four l-histidine bis(fluoride) units. Both differential thermal analysis and temperature-dependent XRD show that the crystals are thermally stable up to 191°C and do not undergo phase transition. The computational Hirshfeld surface analysis of the crystal structure reveals the main intermolecular interactions. Density functional theory has been employed to calculate the ionic interaction energy and electrostatic potential maps and confirm the spontaneity of ionic association at 191°C. The combined experimental and computational results show that the thermal stability of the semi-organic l-histidine bis(fluoride) crystal makes it suitable for nonlinear optical applications in optical sensing and communication systems. Graphical abstract

The Self-Assembly Soluplus Nanomicelles of Nobiletin in Aqueous Medium Based on Solid Dispersion and Their Increased Hepatoprotective Effect on APAP-Induced Acute Liver Injury

“…As shown in the PXRD curves ( Figure 4C ), a great deal of intense peaks ranging from 5° to 35° were observed for Free NOB, indicating the crystalline state of NOB, whereas there was no crystal diffraction peak in the carrier mixture of Soluplus and PVP/PV 64 because of their amorphous nature. 30 , 31 Diffraction peaks with 10°–15° and 20°–25° were still obviously observed in NOB/PM even though their intensities were weaker than those of Free NOB, which indicated the presence of NOB crystals in NOB/PM. However, the weak diffraction peaks (10°–15° and 20°–25°) were disappeared in the NOB/SD formulation, which confirmed that NOB existed an amorphous state in NOB/SD formulation.…”

New polymorphic phase of arachidic acid crystal: structure, intermolecular interactions, low-temperature stability and Raman spectroscopy combined with DFT calculations

“…On the other hand, hydrogen bonds in terms of percentage exhibit a more significant amount in other compounds based on organic molecules such as amino acids and their complexes. 61,62…”

“…On the other hand, hydrogen bonds in terms of percentage exhibit a more signicant amount in other compounds based on organic molecules such as amino acids and their complexes. 61,62 3.3 Group theory and vibrational properties at temperatures of 300 and 100 K 3.3.1 Group-theory analysis. According to group theory, all fundamental vibrations of AA crystal in the B m form are described through the A g , A u , B g and B u irreducible representations of C 2h -factor group.…”

Preparation and Characterization of a Rifampicin Coamorphous Material with Tromethamine Coformer: An Experimental–Theoretical Study

“…However, B3LYP and other popular functionals are unsuitable for studying systems where noncovalent interactions play a key role. ,− On the other hand, new DFT-based functionals have been implemented with empirical corrections for dispersion energy duly to ensure greater accuracy in treating long-range interactions. This is the case of the DFT functional ωB97X-D, which is also robust for its use in the study of the thermochemistry of organic systems. ,− Therefore, a DFT study is performed herein employing the ωB97X-D functional and 6-31G­(d) basis set for the calculations for the individual compounds (RIF and TRIS) and to study interactions in the heterodimer (RIF–TRIS) that constitutes the coamorphous material, contributing to the elucidation of its formation and physical stability. Spectroscopic and thermodynamic data, as well as electronic properties of RIF, TRIS, and the RIF-TRIS heterodimer, were calculated in this work.…”