Spin Transition in Arrays of Gold Nanoparticles and Spin Crossover Molecules

التفاصيل البيبلوغرافية
العنوان: Spin Transition in Arrays of Gold Nanoparticles and Spin Crossover Molecules
المؤلفون: Devid, E. J., Martinho, P. N., Mutta, Venkata Kamalakar, 1979, Salitros, I., Prendergast, U., Dayen, J. F., Meded, V., Lemma, T., Gonzalez-Prieto, R., Evers, F., Keyes, T. E., Ruben, M., Doudin, B., van der Molen, S. J.
المصدر: ACS Nano. 9(4):4496-4507
مصطلحات موضوعية: spin crossover molecules, molecular charge transport devices, self-assembly, gold nanoparticles
الوصف: We investigate if the functionality of spin crossover molecules is preserved when they are assembled into an interfacial device structure. Specifically, we prepare and investigate gold nanoparticle arrays, into which room-temperature spin crossover molecules are introduced, more precisely, [Fe(AcS-BPP)(2)](ClO4)(2), where AcS-BPP = (S)-(4-{[2,6-(dipyrazol-1-yl)pyrid-4-yl]ethynyl}phenyl)ethanethioate (in short, Fe(S-BPP)(2)). We combine three complementary experiments to characterize the molecule-nanoparticle structure in detail. Temperature-dependent Raman measurements provide direct evidence for a (partial) spin transition in the Fe(S-BPP)(2)-based arrays. This transition is qualitatively confirmed by magnetization measurements. Finally, charge transport measurements on the Fe(S-BPP)(2)-gold nanoparticle devices reveal a minimum in device resistance versus temperature, R(T), curves around 260-290 K. This is in contrast to similar networks containing passive molecules only that show monotonically decreasing R(T) characteristics. Backed by density functional theory calculations on single molecular conductance values for both spin states, we propose to relate the resistance minimum in R(T) to a spin transition under the hypothesis that (1) the molecular resistance of the high spin state is larger than that of the low spin state and (2) transport in the array is governed by a percolation model.
URL الوصول: https://research.chalmers.se/publication/218283
http://dx.doi.org/10.1021/acsnano.5b01103
قاعدة البيانات: SwePub
الوصف
تدمد:1936086X
19360851
DOI:10.1021/acsnano.5b01103