{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:56:52Z","timestamp":1760241412583,"version":"build-2065373602"},"reference-count":58,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,2,9]],"date-time":"2018-02-09T00:00:00Z","timestamp":1518134400000},"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 nitronyl nitroxide derivative, 2-phenylethynyl-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-oxyl-3-oxide (1), and two verdazyl derivatives carrying a phenylacetylene unit, 1,5-diphenyl-3-phenylethynyl-6-oxo-1,2,4,5-tetrazin-2-yl (2) and 1,5-diisopropyl-3-phenylethynyl-6-oxo-1,2,4,5-tetrazin-2-yl (3), were synthesized and their packing structures were studied by X-ray crystallographic analysis and magnetically characterized in the solid state. While 1 and 3 had an isolated doublet spin state, 2 formed an antiferromagnetically coupled pair (2J\/kB = \u2212118 K). Density functional theory (DFT) calculations reveal that the spin density polarized in the phenyl group decreases as the dihedral angle between the phenyl ring and radical plane increases.<\/jats:p>","DOI":"10.3390\/molecules23020371","type":"journal-article","created":{"date-parts":[[2018,2,9]],"date-time":"2018-02-09T12:46:27Z","timestamp":1518180387000},"page":"371","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Synthesis and Magnetic Properties of Stable Radical Derivatives Carrying a Phenylacetylene Unit"],"prefix":"10.3390","volume":"23","author":[{"given":"Shogo","family":"Miyashiro","sequence":"first","affiliation":[{"name":"Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomoaki","family":"Ishii","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Youhei","family":"Miura","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3700-9570","authenticated-orcid":false,"given":"Naoki","family":"Yoshioka","sequence":"additional","affiliation":[{"name":"Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,2,9]]},"reference":[{"key":"ref_1","unstructured":"Lahti, P.M. 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