Low frequency Raman spectra and mapping of shear and layer breathing modes of MoSe2 are presented for the first time. We correlate the behavior of these modes with layer number in the materials. The usefulness of low frequency Raman mapping to probe the symmetry, quality, and monolayer presence...
The sharp peaks below 150 cm−1 for the 2.71-eV excitation Figure 3. (a) Raman spectra of bulk MoSe2 taken with the excitation energies indicated. (b) Intensities of A1g, and E2g1 modes and E2g1/A1g, ratio as functions of the excitation energy. Some major optical transition ...
Effects of lower symmetry and dimensionality on Raman spectra in two-dimensionalWSe_2 Photoluminescence Emission and Raman Response of Monolayer MoS2, MoSe2, and WSe2. Opt. Express 2013, 21, 4908-4916.X. Luo et al., Effects of lower... Xin,Luo,Yanyuan,... - 《Physical Review B Condense...
While details of Raman and IR spectra can be used to identify the stacking sequence in specific mate- rials, the widening array of newly discovered 2D materials begs the question of whether or not there are any rules of thumb that can be used to identify the stacking sequence regardless of ...
For instance, absorption spectra provide clear evidence for the formation of a CT complex between a molecule and substrate, such as the emergence of a weak absorption peak at 1,060 nm for rhodamine 6G (R6G) adsorbed on Ag nanoparticles, which is not present in the individual spectra of the...
Raman spectra were taken at the following conditions: (1) fresh sample at 50 ℃ in 100% Ar; (2) after oxygen pretreatment at 200 ℃ in 100% Ar; and (3) during steady state ethylene oxidation at 200 ℃ in 10% C2H4 and 5% O2 after 1, 2, 3 and 4 h of reaction. 2.6. Hydrogen...
Second-order Raman spectra of monolayer MoSe2 are observed by using circularly polarized light for four laser energies, which are resonant with the C exciton. Helicity-dependent Raman spectra show that the overtone mode of a helicity-changing mode observed at 560–610cm1 is a helicity-conserved ...
We uncover strong nanoscale heterogeneities in the Raman spectra of MoSe2 transferred to gold substrates [one near 240 cm-1 (A1′), and others near 287 cm-1 (E′), 340 cm-1, and 995 cm-1], which are not observable with common confocal techniques and appear to imply the presence of ...
the applied computational routines are freely available online through the website. Our numerical results are benchmarked against available experimental data for selected 2D crystals (15 different monolayers) such as MoS2, MoSSe, and MoSe2. The calculated spectra show excellent agreement with experiments...
The observation of Davydov splitting of phonon modes in few-layer TMD films, which arises from interlayer interactions, is also facilitated by resonant excitation of RS spectra21,22. It has been reported for all semiconducting few-layer TMD materials: MoS223, MoSe224, WS225,26, WSe227 and ...