Magneto-structural correlation of cyano-substituted 3-tert-butyl-1-phenyl-1,2,4-benzotriazin-4-yl: spin transition behaviour observed in a 6-cyano derivative

• Published in: New journal of chemistry Vol. 42; no. 12; pp. 9949 - 9955
• Main Authors: Takahashi, Yusuke, Tsuchiya, Naoya, Miura, Youhei, Yoshioka, Naoki
• Format: Journal Article
• Language: English
• Published: CAMBRIDGE Royal Soc Chemistry 2018; Royal Society of Chemistry
• Subjects: Antiferromagnetism; Chemistry; Chemistry, Multidisciplinary; Columnar structure; Crystallography; Magnetic properties; Molecular chains; Phase transitions; Physical Sciences; Rotation; Science & Technology; Spin transition; Substitutes; POLYMERS; DESIGN; TEMPERATURE; THERMOCHROMISM; ORGANIC RADICALS; MAGNETIC-PROPERTIES; EXCHANGE; PEIERLS TRANSITION
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c7nj04534d

New cyano-substituted 3-tert-butylbenzotriazinyls, 7CN and 6CN, were synthesized and their spectroscopic properties and magneto-structural correlation were investigated. The radical 7CN formed a 1D columnar structure and displayed an antiferromagnetic interaction along the column (J = -15.8 cm(-1)). The 6-cyano substituted radical 6CN also formed a 1D columnar structure and exhibited a reversible spin transition at ca. 284 K in the range of 6 K. The molecular arrangements in the high-temperature phase (300 K) and low-temperature phase (263 K) were evaluated by X-ray crystallographic analysis and the molecules slightly rotated while remaining in the 1D columnar structure, resulting in a phase transition. The spin transition behaviour was caused by the structural phase transition, which was consistent with the DSC and computational studies.