Synthesis and spectroscopic characterization of alkali-metal intercalated ZrSe 2

We report on the synthesis and spectroscopic characterization of alkali metal intercalated ZrSe single crystals. ZrSe is produced by chemical vapour transport and then Li is intercalated. Intercalation is performed from the liquid phase (via butyllithium) and from the vapour phase. Raman spectroscopy of intercalated ZrSe reveals phonon energy shifts of the Raman active A and E phonon modes, the disappearance of two-phonon modes and new low wavenumber Raman modes. Angle-resolved photoemission spectroscopy is used to perform a mapping of the Fermi surface revealing an electron concentration of 4.7 × 10 cm . We also perform vapour phase intercalation of K and Cs into ZrSe and observe similar changes in the Raman modes as for the Li case.