High-pressure phase transition in LiBH4

The high-pressure phase transition from ambient pressure α-LiBH4 to high-pressure β-LiBH4 was observed by Raman spectroscopy and X-ray diffraction between 0.8 and 1.1 GPa. The phase boundary between these two phases was mapped over a large range of temperatures using thermal conductivity studies and differential thermal analysis. The structure of the high-pressure phase could not be identified due to small number of experimentally observed reflections, but it was shown that it is different from previously reported theoretical predictions.

Raman spectra of LiBH4 in the region of the phase transition recorded during decompression.Figure optionsDownload as PowerPoint slide