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Updated: Jun 5, 2025
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Effect of different crystallographic properties on the electrical conductivity of two polymorphs of a spin crossover
Rifat Mahbub1, Kayleigh A McElveen2, M Zaid Zaz3
1Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, 900 N 16th St., Lincoln, NE 68588, United States of America.
Abstract:
In this study, the structure and transport properties of two polymorphs, nanoparticles and nanorods, of the iron(II) triazole [Fe(Htrz)2(trz)](BF4) spin crossover complex were compared. Conductive atomic force microscopy was used to map the electrical conductivity of individual nanoparticles and nanorods. The [Fe(Htrz)2(trz)](BF4) nanorods showed significantly higher conductivity compared to nanoparticles. This difference in electrical conductivity is partially associated to the different Fe-N bond lengths in each of the polymorphs, with an inverse relationship between Fe-N bond length and conductivity. Transport measurements were done on the nanorods for both high spin (at 380 K) and low spin (at 320 K) states under dark and illuminated conditions. The conductance is highest for the low spin state under dark conditions. In illumination, the conductance change is much diminished.
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