{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T19:34:19Z","timestamp":1790710459454,"version":"4.1.0"},"reference-count":57,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,5,23]],"date-time":"2025-05-23T00:00:00Z","timestamp":1747958400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003453","name":"Natural Science Foundation of Guangdong Province","doi-asserted-by":"publisher","award":["2022A1515011145"],"award-info":[{"award-number":["2022A1515011145"]}],"id":[{"id":"10.13039\/501100003453","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003453","name":"Natural Science Foundation of Guangdong Province","doi-asserted-by":"publisher","award":["202102080023"],"award-info":[{"award-number":["202102080023"]}],"id":[{"id":"10.13039\/501100003453","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003453","name":"Natural Science Foundation of Guangdong Province","doi-asserted-by":"publisher","award":["202201020166"],"award-info":[{"award-number":["202201020166"]}],"id":[{"id":"10.13039\/501100003453","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Science and Technology Research Project of Guangzhou","award":["2022A1515011145"],"award-info":[{"award-number":["2022A1515011145"]}]},{"name":"Science and Technology Research Project of Guangzhou","award":["202102080023"],"award-info":[{"award-number":["202102080023"]}]},{"name":"Science and Technology Research Project of Guangzhou","award":["202201020166"],"award-info":[{"award-number":["202201020166"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>We report the synthesis, structural characterization, and magnetic properties of three pentacoordinate Co(II) complexes [CoX(dppb)2]X (X = Cl (1Cl), Br (2Br), and I (3I)) supported by the bidentate phosphine ligand 1,2-bis(diphenylphosphino)benzene (dppb). Single-crystal X-ray diffraction reveals that all three complexes adopt similar vacant octahedron (C4v) geometries with the halide ligand in one axial position. Magnetic studies demonstrate that these complexes exhibit field-induced slow magnetic relaxation behaviors, with positive D values of 25.3(2), 21.6(1), and 19.4(2) cm\u22121 for 1Cl, 2Br, and 3I, respectively. Detailed analysis of the relaxation dynamics reveals that Raman processes dominate at higher temperatures, with systematic variations in relaxation parameters across the series. The systematic variations in magnetic anisotropy and slow magnetic relaxation behaviors of the three complexes correlate with the decreasing electronegativity of the halide ligands.<\/jats:p>","DOI":"10.3390\/molecules30112295","type":"journal-article","created":{"date-parts":[[2025,5,23]],"date-time":"2025-05-23T12:24:18Z","timestamp":1748003058000},"page":"2295","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Field-Induced Slow Magnetic Relaxation in Pentacoordinate Co(II) Complexes: Tuning Magnetic Anisotropy Through Halide Substitution"],"prefix":"10.3390","volume":"30","author":[{"given":"Hong-Yao","family":"Guo","sequence":"first","affiliation":[{"name":"School of Chemistry and Chemical Engineering\/Institute of Clean Energy and Materials, Guangzhou Higher Education Mega Center, Guangzhou University, No. 230 Wai Huan Xi Road, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0698-0719","authenticated-orcid":false,"given":"Wei-Quan","family":"Lin","sequence":"additional","affiliation":[{"name":"School of Chemistry and Chemical Engineering\/Institute of Clean Energy and Materials, Guangzhou Higher Education Mega Center, Guangzhou University, No. 230 Wai Huan Xi Road, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9355-5643","authenticated-orcid":false,"given":"Ji-Dong","family":"Leng","sequence":"additional","affiliation":[{"name":"School of Chemistry and Chemical Engineering\/Institute of Clean Energy and Materials, Guangzhou Higher Education Mega Center, Guangzhou University, No. 230 Wai Huan Xi Road, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1005","DOI":"10.1002\/cjoc.202000090","article-title":"Development of Single-Molecule Magnets","volume":"38","author":"Shao","year":"2020","journal-title":"Chin. 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