Changing Single-Molecule Magnet Properties of a Windmill-Like Distorted Terbium(III) α-Butoxy-Substituted Phthalocyaninato Double-Decker Complex by Protonation/Deprotonation

Yoji Horii; Yusuke Horie; Keiichi Katoh; Brian K Breedlove; Masahiro Yamashita

doi:10.1021/acs.inorgchem.7b02124

Changing Single-Molecule Magnet Properties of a Windmill-Like Distorted Terbium(III) α-Butoxy-Substituted Phthalocyaninato Double-Decker Complex by Protonation/Deprotonation

Inorg Chem. 2018 Jan 16;57(2):565-574. doi: 10.1021/acs.inorgchem.7b02124. Epub 2017 Oct 13.

Authors

Yoji Horii¹, Yusuke Horie¹, Keiichi Katoh¹, Brian K Breedlove¹, Masahiro Yamashita^{1

2

3}

Affiliations

¹ Department of Chemistry, Graduate School of Science, Tohoku University , 6-3, Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan.
² WPI Research Center, Advanced Institute for Materials Research, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
³ School of Materials Science and Engineering, Nankai University , Tianjin 300350, China.

PMID: 29027796
DOI: 10.1021/acs.inorgchem.7b02124

Abstract

Synthesis, structures, and magnetic properties of α-butoxy-substituted phthalocyaninato double-decker complexes Tb(α-obPc)₂ (1^-) (α-obPc: dianion of 1,4,8,11,15,18,22,25-octa(n-butoxy)phthalocyaninato) with protonated (1H), deprotonated (1[HDBU]), and diprotonated forms (1H₂⁺) are discussed. X-ray analysis was used to confirm the position of the proton in 1H, and it was revealed that the protonation induced asymmetric distortion in 1H. In contrast, 1[HDBU] was distorted in a highly symmetric windmill-like fashion. 1H is arranged in a slipped column array in the crystal packing, whereas 1[HDBU] is arranged in a one-dimensional fashion, in which the magnetic easy axes of 1[HDBU] lie along the same line. From direct-current (dc) magnetic measurements, ferromagnetic Tb-Tb interactions occur in both 1H and 1[HDBU], and magnetic hysteresis was observed. However, the area of the magnetic hysteresis in 1[HDBU] is larger than that in 1H, meaning that magnetic relaxation time (τ) is longer in 1[HDBU]. In addition, the results of alternating-current magnetic measurements in a zero dc magnetic field indicate that τ of 1[HDBU] is longer as compared to 1H. In other words, protonation/deprotonation affects not only the molecular structures and crystal packing but also the single-molecule magnet properties.