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Updated: Feb 24, 2026

Author Spotlight: A Rapid, Microwave-Assisted Hydrothermal Synthesis Of Nickel Hydroxide Nanosheets
Published on: August 18, 2023
High pressure studies on bis(l-histidinate)nickel(II) monohydrate
J R Maia1, J A Lima2, P T C Freire2
1Faculdade de Filosofia Dom Aureliano Mattos, Universidade Estadual do Ceará, CEP 63.900-000 Limoeiro do Norte, CE, Brazil.
Abstract:
Raman spectra of bis(l-histidinate)nickel(II) monohydrate crystal were obtained for pressures up to 9.5GPa. Our results show the disappearance of some of the Raman modes and the appearance of other modes. These modifications evidence that the sample undergoes phase transitions at around 0.8 and 3.2GPa. The role played by the Ni ions and hydrogen bonds in the dynamics of the phase transitions is discussed. Under decompression, down to atmospheric pressure, the original Raman spectra are recovered, showing that both phase transitions are fully reversible.
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