Measured thermodynamic states of Raman spectra of supercritical methanol plotted on (a) phase diagram and (b) phase diagram. Measurements are carried out along the isotherm line of reduced temperature by increasing pressures.
Typical example of Raman spectrum of the liquid methanol at room temperature condition.
Raman spectra of stretching mode of methanol in the supercritical state at the reduced temperature (522.9 K). The measured pressures are written in the left side and the corresponding reduced densities are also written at the right side.
Density dependencies of (a) peak position and (b) spectral width of Raman spectrum of stretching mode. Solid lines are to guide the eye.
Spectral shift (%) from the isolated condition as a function of the Onsager reaction field.
Spectral shifts as a function of packing fraction and reduced density . Solid triangles, open circles, and solid circles are repulsive, net, and attractive shifts, respectively.
Calculated homogeneous inhomogeneous widths.
(a) Attractive shift as a function of reduced density , analyzed by the Onsager reaction field. (b) Local density enhancement of supercritical methanol at obtained from the reaction field analysis. Units of the local density enhancement and bulk density are number density in the volume of . The corresponding reduced density is represented in the top axis.
Local density enhancements of supercritical methanol obtained from the analysis of the NMR data performed at (Ref. 73).
(a) Attractive shift as a function of local density. The attractive shifted amount is derived from the curve of Fig. 8(a), and the local density is given by the summation of bulk density and local density enhancement. (b) The difference between the actual local density and averaged local density as a function of bulk density. (c) Fluctuation of local density as a function of bulk density.
Fluctuation of bulk density obtained from the isothermal compressibility, which is given by the state of equation in relation to .
Peak positions and spectral widths of stretching mode of neat supercritical methanol measured at 522.9 K as a function of density.
Parameters of stretching mode of methanol molecule.
Shifted amounts from the isolated condition of stretching mode as a function of density and/or packing fraction. Total, repulsive, and attractive shifts are obtained as experimental, calculated, and empirical values, respectively.
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