Evaluation of Electronic Structure of Prussian Blue Analogue RbMn[Fe(CN)₆] in Temperature-Induced Phase Transition Phenomena

In this study, the electronic state of RbMn[Fe(CN)6], a type of Prussian blue analogs (PBAs), was reported using X-ray absorption spectroscopy, focusing on the K absorption edge of Mn. It is known that many PBAs exhibit a first-order phase transition when the temperature changes, however interestingly, the present experimental results show that the spectrum of the Mn K-edge does not exhibit a simple first-order phase transition. This result indicates the possibility of unraveling the previously unclear phase relationship between the electronic and crystal structures of PBAs and their complex physical properties.