Area II. Diruthenium Alkynyls as Wires and Devices
Our earlier work on both the mono-alkynyl and bis-alkynyl Ru2 compounds supported by N,N'-bidentate bridging ligands revealed their rich redox activity and small energy gaps ranging from 1.2 to 1.6 eV. The electronic couplings between two Ru2 units across oligoyn-diyls were extensively probed using both voltammetry and spectroelectrochemistry, where a remarkably small attenuation (g) was deduced. The efficiency of Ru2 fragments in mediating electronic coupling was similarly probed using Fc(C≡C)m as the axial ligands. While we are still interested in uncovering new diruthenium species, our recent effort places more emphasis in using these diruthenium compounds as the active materials in devices, such as flash memory, through collaboration with device engineers at NIST.
(a) Diruthenium alkynyls and supporting Ligands; (b) Molecular structure of [Ru2(ap)4]2(m-C12); (c) Distance dependence of Had in [Ru2(ap)4]2(m-C2m) (m = 2 - 9)
Selected References:
General overview: Ren, T. Organometallics 2005, 24, 4854-4870; "Diruthenium s-Alkynyl Compounds: A New Class of Conjugated Organometallics"; http://dx.doi.org/10.1021/om050452q.
Recent Publications:
Cao, Z.; Xi, B.; Jodoin, D. S.; Zhang, L.; Cummings, S. P.; Gao, Y.; Tyler, S. F.; Fanwick, P. E.; Crutchley, R. J.; Ren, T. J. Am. Chem. Soc. 2014, 136, 12174–12183; "Diruthenium-Polyyn-diyl-Diruthenium Wires: Electronic Couplings in the Long Distance Regime"; http://dx.doi.org/10.1021/ja507107t.
Zhu, H.; Pookpanratana, S. J.; Bonevich, J. E.; Natoli, S. N.; Hacker, C. A.; Ren, T.; Suehle, J. S.; Richter, C. A.; Li, Q. ACS Appl. Mater. Interfaces 2015, 7, 27306-27313; "Redox-Active Molecular Nanowire Flash Memory for High-Endurance and High-Density Non-Volatile Memory Applications"; http://dx.doi.org/10.1021/acsami.5b0851.