相关论文: Raman spectra of L-leucine crystals
We present a Raman spectroscopy investigation of the vibrational properties of L-histidine crystals at low temperatures. The temperature dependence of the spectra show discontinuities at 165 K, which we identify with modifications in the…
The study of single-crystal Raman spectra of a series of crystalline secondary amides (acetanilide, methacetin, phenacetine, orthorhombic and monoclinic polymorphs of paracetamol) as well as simple amides formanilide and benzanilide in the…
Pressure-dependent Raman scattering studies in the range 0.0 -- 32 kbar were carried out in L-alanine in order to investigate its external mode phonon spectra in relation to the phase transitions in the crystal. A careful analysis of the…
We have performed for the first time micro-Raman studies of lysozyme crystals for the temperatures lower than the room one (in the range 282-300K). Anomalous temperature dependence of the positions of Raman scattering bands has been…
The effect of ultraviolet radiation (275 nm) on the Raman spectra of amino acid microcrystals: alanine, glycine, tryptophan was studied. The position of some lines in the spectra after irradiation has slightly shifted towards high energies.…
1H RAMPS solid state NMR and 13C CP/MAS spectra of D- and L- alanine crystals were measured at temperature ranging from 220K to 295K. Some major points are as follows: (1)alpha-H and protons in the methyl group showed a spin-spin coupling…
We present a detailed study on the temperature-dependent THz spectra of the polycrystalline amino acids L-serine and L-cysteine for wave numbers from 20 to 120 cm-1 and temperatures from 4 to 300 K. Even though the structure of these two…
Raman scattering experiments have been carried out on single crystals of Nd$_{0.5}$Sr$_{0.5}$MnO$_3$ as a function of temperature in the range of 320-50 K, covering the paramagnetic insulator-ferromagnetc metal transition at 250 K and the…
The results of polarization-dependent Raman spectroscopy of single-crystalline LiVO$_2$ exhibiting transition to a diamagnetic state below $T_c \sim $500K are reported. Our measurements clearly detect additional peaks in the low-temperature…
We report on an inelastic (Raman) light scattering study of the local structure of amorphous GeTe films. A detailed analysis of the temperature-reduced Raman spectra has shown that appreciable structural changes occur as a function of…
A Raman scattering spectroscopy study is reported through all four phases of a (K0.5Na0.5)NbO3 crystal and ((K0.5Na0.5)1-xLix)NbO3 for x=0.02 and 0.03. The transitions among the ferroelectric phases in the Li-free crystal are homogeneous…
We present new kinetics data on the radiolytic destruction of amino acids measured in situ with infrared spectroscopy. Samples were irradiated at 15, 100, and 140 K with 0.8-MeV protons, and amino-acid decay was followed at each temperature…
Antibody drugs are usually formulated as highly-concentrated solutions, which would easily generate oligomer and aggregation, resulting in loss of efficacy. Although low pH increases the colloidal dispersion of antibodies, acid denaturation…
We present theoretical calculations of the Raman and IR spectra, as well as electronic properties at zero and finite temperature to elucidate the crystal structure of phase III of solid molecular hydrogen. We find that anharmonic finite…
The structural changes in Sr(0.66)Ba(0.34)Nb2O6 single crystal fibers when the temperature decreases from 295 to 10 K is investigated by dielectric constant measurements and Raman spectroscopy. The anomaly observed in the plot of e is…
Raman and Infrared (IR) spectra of an underdoped La_{1.90}Sr_{0.10}CuO_{4} single crystal have been measured as a function of temperature. Both techniques provide unconventional low-energy spectra. The IR conductivity exhibits features…
A vast amount of Raman spectroscopic data, obtained using diamond anvil cell technique under in situ high pressure-temperature conditions, has been used for mapping the phase transitions of hydrogen in the temperature range of 300 K to 900…
We revisit here how Raman spectroscopy can be used to estimate the H content in hard hydrogenated amorphous carbon layers. The H content was varied from 2 at.% to 30 at.%, using heat treatments of a a-C:H, from room temperature to 1300 K…
L-band spectroscopy is a powerful probe of cool low-gravity atmospheres: The P, Q, and R branch fundamental transitions of methane near 3.3 $\mu$m provide a sensitive probe of carbon chemistry; cloud thickness modifies the spectral slope…
We report a temperature-dependent Raman scattering investigation of DyScO3 and GdScO3 single crystals from room temperature up to 1200 {\deg}C. With increasing temperature, all modes decrease monotonously in wavenumber without anomaly,…