Abstract
We have studied the local structure of layered Nax(NH3)yMoSe2 system by Mo K-edge extended X-ray absorption fine structure (EXAFS) measurements performed as a function of temperature. We find that molecular intercalation in MoSe2 largely affects the Mo-Se network while Mo-Mo seems to sustain small changes. The Einstein temperature (ΘE of Mo-Mo distance hardly changes (∼264 K) indicating that bond strength of this distance remains unaffected by intercalation. On the other hand, Mo-Se distance suffers a softening, revealed by the decrease of ΘE from ∼364 K to ∼350 K. The results indicate that Na+ ion transported by NH3 molecules may enter between the two MoSe-layers resulting reduced Se-Se coupling. Therefore, increased hybridization between Se 4p and Mo 4d orbitals due to inter-layer disorder is the likely reason of metallicity in intercalated MoSe2 and superconductivity at low temperature.
Original language | English |
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Pages (from-to) | 70-74 |
Number of pages | 5 |
Journal | Journal of Physics and Chemistry of Solids |
Volume | 111 |
DOIs | |
Publication status | Published - Dec 2017 |
Keywords
- Dichalcogenides
- Intercalation effect
- Local disorder
- Superconductivity
ASJC Scopus subject areas
- Chemistry(all)
- Materials Science(all)
- Condensed Matter Physics