The dynamic interplay between intramolecular and intermolecular interactions in mononuclear manganese(iii) SCO complexes. Issue 17 (14th April 2021)

• Record Type: Journal Article
• Authors: Qin, Chun-Yan; Zhao, Sheng-Ze; Wu, Hua-Yu; Li, Yong-Hua; Wang, Zi-Kun; Wang, Zheng; Wang, Shi
• Is Part Of: Dalton transactions. Volume 50:Issue 17(2021)
• Page Start: 5899
• Page End: 5910
• Publication Date: 2021-04-14
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d0dt04109b
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Spin crossover in Mn(iii ) ions is the most rare event. Changing the size of the anions from PF6 −, AsF6 −, SbF6 − to BF4 −, ClO4 −, Cl −, Br −, and I − led to a significant change of the overall crystal packing and furthermore the Mn(iii ) spin state. Abstract : The effect of counter anions on thermally induced manganese(iii )-based SCO within the [Mn(5-F-sal-N-1, 5, 8, 12)]Y family has been investigated. All the complexes are crystallized without any lattice solvents. Crystal packing and intermolecular forces influence the spin-state stabilization and spin-transition profiles. Magnetic measurements indicate that salts with octahedral anions, [Mn(5-F-sal-N-1, 5, 8, 12)]PF6 (1 ), [Mn(5-F-sal-N-1, 5, 8, 12)]AsF6 (2 ) and [Mn(5-F-sal-N-1, 5, 8, 12)]SbF6 (3 ), show HS electronic configurations between 2 and 300 K, and there exist π–π stackings between the phenyl groups from the neighboring [Mn(5-F-sal-N-1, 5, 8, 12)] + cations. As for the tetrahedral anions, complex [Mn(5-F-sal-N-1, 5, 8, 12)]BF4 (4 ) exhibits a gradual and incomplete spin conversion. Complex [Mn(5-F-sal-N-1, 5, 8, 12)] ClO4 (5 ) shows a nearly complete SCO with T 1/2 = 100 K. The remaining salts with spherical anions form Nam –H⋯X (X = Cl, Br, I) hydrogen bonds between Mn(iii ) cations and counterions. Complexes [Mn(5-F-sal-N-1, 5, 8, 12)]Cl (6 ) and [Mn(5-F-sal-N-1, 5, 8, 12)] Cl0.28 Br0.72 (7 ) feature gradual SCO behaviors with T 1/2 = 220 K and 235 K, respectively. Complex [Mn(5-F-sal-N-1, 5, 8, 12)]I (8 ) exhibits a more gradual spin conversion and is far from a complete HS state with a χ M T value of 1.89 cm 3 mol −1 K at 400 K.