Carboxylic acid functionalized spin-crossover iron(II) grids for tunable switching and hybrid electrode fabrication

Shiga, Takuya; Sato, Yamato; Tachibana, Minami; Sato, Hiroki; Matsumoto, Takuto; Sagayama, Hajime; Kumai, Reiji; Murakami, Youichi; Newton, Graham N.; Oshio, Hiroki

Abstract

Two carboxyl-substituted iron(II) grids, one protonated, [Fe4(HL)4](BF4)4·4MeCN·AcOEt (1), and the other deprotonated, [Fe4(L)4]·DMSO·EtOH (2), where H2L = 4-{4,5-bis[6-(3,5-dimethylpyrazol-1-yl)pyrid-2-yl]-1H-imidazol-2-yl}benzoic acid, were synthesized. Single-crystal X-ray structure analyses reveal that both complexes have a tetranuclear [2 × 2] grid structure. 1 formed one-dimensional chains through intermolecular hydrogen bonds between the carboxylic acid units of neighboring grids, while 2 formed two-dimensional layers stabilized by π–π-stacking interactions. 1 showed spin transition between the 3HS-1LS and 1.5HS-2.5LS states around 200 K, while 2 showed spin-crossover between the 4LS and 2LS-2HS states above 300 K. A modified indium–tin oxide (ITO) electrode was fabricated by soaking the ITO in a solution of 1. The resultant electrode showed reversible redox waves attributed to the original redox processes of iron(II)/iron(III).

Citation

Shiga, T., Sato, Y., Tachibana, M., Sato, H., Matsumoto, T., Sagayama, H., …Oshio, H. (2018). Carboxylic acid functionalized spin-crossover iron(II) grids for tunable switching and hybrid electrode fabrication. Inorganic Chemistry, 57(22), 14013-14017. https://doi.org/10.1021/acs.inorgchem.8b01856

• Journal Article Type: Article
• Acceptance Date: Oct 26, 2018
• Online Publication Date: Oct 31, 2018
• Publication Date: Oct 31, 2018
• Deposit Date: Nov 8, 2018
• Publicly Available Date: Nov 1, 2019
• Journal: Inorganic Chemistry
• Print ISSN: 0020-1669
• Electronic ISSN: 1520-510X
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 57
• Issue: 22
• Pages: 14013-14017
• DOI: https://doi.org/10.1021/acs.inorgchem.8b01856
• Keywords: Spin crossover; Magnetism; Switchable molecules; Iron; Polynuclear complex
• Public URL: https://nottingham-repository.worktribe.com/output/1236898
• Publisher URL: https://pubs.acs.org/doi/10.1021/acs.inorgchem.8b01856
• Additional Information: This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in Inorganic Chemistry, copyright © American Chemical Society after peer review. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acs.inorgchem.8b01856.
• Contract Date: Nov 8, 2018