TY - JOUR
T1 - Spin-Crossover in Supramolecular Iron(II)-2,6-bis(1 H-Pyrazol-1-yl)pyridine Complexes
T2 - Toward Spin-State Switchable Single-Molecule Junctions
AU - Kuppusamy, Senthil Kumar
AU - Mizuno, Asato
AU - García-Fuente, Amador
AU - Van Der Poel, Sebastiaan
AU - Heinrich, Benoît
AU - Ferrer, Jaime
AU - Van Der Zant, Herre S.J.
AU - Ruben, Mario
PY - 2022
Y1 - 2022
N2 - Spin-crossover (SCO) active iron(II) complexes are an integral class of switchable and bistable molecular materials. Spin-state switching properties of the SCO complexes have been studied in the bulk and single-molecule levels to progress toward fabricating molecule-based switching and memory elements. Supramolecular SCO complexes featuring anchoring groups for metallic electrodes, for example, gold (Au), are ideal candidates to study spin-state switching at the single-molecule level. In this study, we report on the spin-state switching characteristics of supramolecular iron(II) complexes 1 and 2 composed of functional 4-([2,2′-bithiophen]-5-ylethynyl)-2,6-di(1H-pyrazol-1-yl)pyridine (L1) and 4-(2-(5-(5-hexylthiophen-2-yl)thiophen-2-yl)ethynyl)-2,6-di(1H-pyrazol-1-yl)pyridine (L2) ligands, respectively. Density functional theory (DFT) studies revealed stretching-induced spin-state switching in a molecular junction composed of complex 1, taken as a representative example, and gold electrodes. Single-molecule conductance traces revealed the unfavorable orientation of the complexes in the junctions to demonstrate the spin-state dependence of the conductance.
AB - Spin-crossover (SCO) active iron(II) complexes are an integral class of switchable and bistable molecular materials. Spin-state switching properties of the SCO complexes have been studied in the bulk and single-molecule levels to progress toward fabricating molecule-based switching and memory elements. Supramolecular SCO complexes featuring anchoring groups for metallic electrodes, for example, gold (Au), are ideal candidates to study spin-state switching at the single-molecule level. In this study, we report on the spin-state switching characteristics of supramolecular iron(II) complexes 1 and 2 composed of functional 4-([2,2′-bithiophen]-5-ylethynyl)-2,6-di(1H-pyrazol-1-yl)pyridine (L1) and 4-(2-(5-(5-hexylthiophen-2-yl)thiophen-2-yl)ethynyl)-2,6-di(1H-pyrazol-1-yl)pyridine (L2) ligands, respectively. Density functional theory (DFT) studies revealed stretching-induced spin-state switching in a molecular junction composed of complex 1, taken as a representative example, and gold electrodes. Single-molecule conductance traces revealed the unfavorable orientation of the complexes in the junctions to demonstrate the spin-state dependence of the conductance.
UR - http://www.scopus.com/inward/record.url?scp=85129115176&partnerID=8YFLogxK
U2 - 10.1021/acsomega.1c07217
DO - 10.1021/acsomega.1c07217
M3 - Article
AN - SCOPUS:85129115176
VL - 7
SP - 13654
EP - 13666
JO - ACS Omega
JF - ACS Omega
IS - 16
ER -