Synthesis and Characterization of Cu-Ni Mixed Metal Paddlewheels Occurring in the Metal-Organic Framework DUT-8(Ni0.98Cu0.02) for Monitoring Open-Closed-Pore Phase Transitions by X-Band Continuous Wave Electron Paramagnetic Resonance Spectroscopy

Mendt M, Ehrling S, Senkovska I, Kaskel S, Poeppl A (2019)

Publication Type: Journal article

Publication year: 2019

Journal

Inorganic Chemistry American Chemical Society

Book Volume: 58

Pages Range: 4561-4573

Journal Issue: 7

DOI: 10.1021/acs.inorgchem.9b00123

Abstract

A Cu 2+ -doped metal-organic framework (DUT-8(Ni 0.98 Cu 0.02 ), M 2 (NDC) 2 DABCO, M = Ni, Cu, NDC = 2,6-napththalene dicarboxylate, DABCO = 1,4-diazabicyclo[2.2.2]octane, DUT = Dresden University of Technology) was synthesized in the form of large (>1 μm) and small crystals (<1 μm) to analyze their switchability by X-band continuous wave (cw) electron paramagnetic resonance (EPR) spectroscopy. The large crystals are flexible and in a porous open pore (op) phase after solvation in N,N-dimethylformamide (DMF), but in the activated solvent-free form, a nonporous closed pore (cp) phase forms. EPR measurements of the rigid Ni-free DUT-8(Cu) show a characteristic electron spin S = 1 room temperature signal of the antiferromagnetically coupled Cu 2+ -Cu 2+ paddlewheel building unit of this metal-organic framework. None of the mixed metal DUT-8(Ni 0.98 Cu 0.02 ) materials showed comparable signals, indicating the absence of dimeric Cu 2+ -Cu 2+ paddlewheel units in the materials. Instead, characteristic electron spin S = 3/2 signals are detected for all DUT-8(Ni 0.98 Cu 0.02 ) samples at temperatures T < 77 K, which can be assigned to ferromagnetically coupled mixed metal Ni 2+ -Cu 2+ paddlewheel units. Those signals differ characteristically for the op and cp phase and enable monitoring the reversible op-cp transition during the de-/adsorption of DMF.

Involved external institutions

Universität Leipzig DE Germany (DE) Technische Universität Dresden DE Germany (DE)

How to cite

APA:

Mendt, M., Ehrling, S., Senkovska, I., Kaskel, S., & Poeppl, A. (2019). Synthesis and Characterization of Cu-Ni Mixed Metal Paddlewheels Occurring in the Metal-Organic Framework DUT-8(Ni0.98Cu0.02) for Monitoring Open-Closed-Pore Phase Transitions by X-Band Continuous Wave Electron Paramagnetic Resonance Spectroscopy. Inorganic Chemistry, 58(7), 4561-4573. https://doi.org/10.1021/acs.inorgchem.9b00123

MLA:

Mendt, Matthias, et al. "Synthesis and Characterization of Cu-Ni Mixed Metal Paddlewheels Occurring in the Metal-Organic Framework DUT-8(Ni0.98Cu0.02) for Monitoring Open-Closed-Pore Phase Transitions by X-Band Continuous Wave Electron Paramagnetic Resonance Spectroscopy." Inorganic Chemistry 58.7 (2019): 4561-4573.

BibTeX: Download