{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T10:08:43Z","timestamp":1790158123550,"version":"4.1.0"},"reference-count":58,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T00:00:00Z","timestamp":1790035200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>A novel organic\u2013inorganic ionic crystal 2,4-diamino-6-phenyl-1,3,5-triaziniumperchlorate (C9H10N5+\u00b7ClO4\u2212) was synthesized via the reaction of benzoguanamine with perchloric acid. Its structure was affined by single-crystal XRD and characterized by UV-Vis and FT-IR spectroscopies. It crystallizes in a monoclinic system, with P21\/c space group and lattice parameters of a = 13.7975 (6), b = 5.0711 (2), c = 16.6471 (9) \u00c5, and \u03b2 = 91.869 (2) \u00b0 and a cell volume of V = 1164.15 (9) \u00c53. Additionally, the 3D-supramolecular network illustrates a supramolecular layer-by-layer arrangement. The two-dimensional fingerprint plots and Hirshfeld surface analysis showed that H\u2219\u2219\u2219O\/O\u2219\u2219\u2219H dominates the interactions, contributing with 33.4%. The UV-Vis spectrum revealed two strong absorption bands at 204 and 247nm, indicating \u03c0\u2192\u03c0* and n\u2192\u03c0* electronic transitions, respectively, which were corroborated by TD-DFT calculations. FT-IR spectroscopy confirmed key vibrational modes consistent with triazinium cations and perchlorate anions, demonstrating strong agreement with the affined structure. TGA\/DTG demonstrated enhanced thermal stability until 290 \u00b0C compared to benzoguanamine, with a four-stage degradation profile, illustrating robust thermal resilience. Moreover, BSSE-corrected interaction-energy calculations revealed that the charge-assisted cation\u2013anion N-H\u00b7\u00b7\u00b7O hydrogen bond is the main cohesive force in the crystal, with a strong stabilization energy of \u2212248.8 kJ mol\u22121, while \u03c0-associated contacts mainly contribute to layered supramolecular packing. C9H10N5+\u00b7ClO4\u2212 exhibits enhanced NLO properties in comparison to urea, due to the cooperative effect of ionic hydrogen bonding and ordered \u03c0-stacking.<\/jats:p>","DOI":"10.3390\/molecules31193369","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T15:28:43Z","timestamp":1790090923000},"page":"3369","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Synthesis, Crystal Structure, Hirshfeld Surface, Vibrational Thermal Analyses, and NLO Properties of a New Hybrid Material: 2,4-Diamino-6-Phenyl-1,3,5-Triazinium Perchlorate, Supported by DFT Calculations"],"prefix":"10.3390","volume":"31","author":[{"given":"Louiza","family":"Ouksel","sequence":"first","affiliation":[{"name":"Laboratory of Electrochemistry and Materials (LEM), Department of Process Engineering, Faculty of Technology, University Ferhat Abbas Setif-1, S\u00e9tif 19000, Algeria"},{"name":"Department of Nature and Life Sciences, Faculty of Biology, University Ferhat Abbas Setif-1, S\u00e9tif 19000, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Rima","family":"Kiche","sequence":"additional","affiliation":[{"name":"Laboratory of Electrochemistry and Materials (LEM), Department of Process Engineering, Faculty of Technology, University Ferhat Abbas Setif-1, S\u00e9tif 19000, Algeria"},{"name":"Mechatronics Laboratory (LMETR)\u2014E1764200, Optics and Precision Mechanics Institute, University Ferhat Abbas S\u00e9tif-1, S\u00e9tif 19000, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1099-0004","authenticated-orcid":false,"given":"Lotfi","family":"Boudjema","sequence":"additional","affiliation":[{"name":"Mechatronics Laboratory (LMETR)\u2014E1764200, Optics and Precision Mechanics Institute, University Ferhat Abbas S\u00e9tif-1, S\u00e9tif 19000, Algeria"},{"name":"Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK"},{"name":"ICAMM Lab\u2014Independent Laboratory for Molecular Modeling and Materials Research, F-13013 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Hakima Ait","family":"Youcef","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Electrochimie, d\u2019Ing\u00e9nierie Mol\u00e9culaire et de Catalyse Redox (LEIMCR), Facult\u00e9 de Technologie, University Ferhat Abbas S\u00e9tif-1, S\u00e9tif 19000, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2622-2384","authenticated-orcid":false,"given":"Abdeltif","family":"Amrane","sequence":"additional","affiliation":[{"name":"\u00c9cole Nationale Sup\u00e9rieure de Chimie de Rennes, University Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)\u2014UMR 6226, F-35000 Rennes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thierry","family":"Roisnel","sequence":"additional","affiliation":[{"name":"University Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)\u2014UMR 6226, F-35000 Rennes, France"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Riadh","family":"Bourzami","sequence":"additional","affiliation":[{"name":"Mechatronics Laboratory (LMETR)\u2014E1764200, Optics and Precision Mechanics Institute, University Ferhat Abbas S\u00e9tif-1, S\u00e9tif 19000, Algeria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Lin, H., Liu, W., and Wu, X. 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