Pressure Broadening Measurements of J=6⇒7 Rotational Line of the t-Butyl Cyanide Molecule

Self-broadened width of J = 6⇒7 rotational line in the ground state of t-butyl cyanide molecule has been measured at room temperature. The measurements of the linewidth as a function of the gas pressure were carried out with home-made spectrometer at the frequency ν$\text{}_{0}$ = 38 498.308 MHz. The mean value of the pressure-broadening coefficient c = 76.9 ± 0.6 MHz Torr$\text{}^{-1}$ was obtained

TEMPERATURE DEPENDENCE OF PRESSURE BROADENED LINEWIDTH OF J =1 = O ROTATIONAL TRANSITION OF CH3C 14 N MOLECULE MIXED WITH OCS AND H2 MOLECULE

The temperature dependence of the pressure-broadening parameters of the J = 1 O rotational transition of OCS and H2 in the ground vibrational state of CH3C 14 N molecule is measured in the temperature range between 248 and 293 K. The line shape of the absorption is recorded with a Stark modulated microwave spectrometer. Using least squares fits of the data to the Voigt line function, several contributions to the linewidth have been deduced. The experimental results are compared with the calculated results using Murphy and Boggs collision broadening theory. The pressure-broadening parameters CW (x) of the gas mixture CH3CN+OCS and CH3CN-+H2 are 14.05f 0.30 MHz/Tr, 9.15f 0.12 MHz/Tr, respectively and the temperature dependence parameters a are -0.90 ± 0.07 and -0.77 ± 0.08

Collisional Broadening of the J=7 ⇐ 6 Transition of t-Butyl Cyanide by CH3\text{}_{3}CN, OCS, CO2\text{}_{2} and Helium

Experimental studies of the broadening of the absorption line J = 6 ⇒ 7 of (CH$\text{}_{3}$)$\text{}_{3}$CCN due to collisions with the foreign perturbers He, CO$\text{}_{2}$, OCS, and CH$\text{}_{3}$CN have been carried out. The magnitude of the broadening coefficients reflects the type of interactions occurring in the molecular collisions. It has been concluded that the dipole-dipole and dipole-quadrupole interactions are predominant in the (CH$\text{}_{3}$)$\text{}_{3}$CCN admixed with CH$\text{}_{3}$CN and OCS. In the collisions between (CH$\text{}_{3}$)$\text{}_{3}$CCN and CO$\text{}_{2}$ the dipole-quadrupole interactions are present whereas the He perturbed by (CH$\text{}_{3}$)$\text{}_{3}$CCN exhibits dispersive type of interactions

Temperature Dependence of Pressure Broadened Linewidth of J = 1 ⇐ 0 Rotational Transition of CH3\text{}_{3}C14\text{}_{14}N Molecule Mixed with OCS and H2\text{}_{2} Molecule

The temperature dependence of the pressure-broadening parameters of the J = 1 ⇐ 0 rotational transition of OCS and H$\text{}_{2}$ in the ground vibrational state of CH$\text{}_{3}$C$\text{}_{14}$N molecule is measured in the temperature range between 248 and 293 K. The line shape of the absorption is recorded with a Stark modulated microwave spectrometer. Using least squares fits of the data to the Voigt line function, several contributions to the linewidth have been deduced. The experimental results are compared with the calculated results using Murphy and Boggs collision broadening theory. The pressure-broadening parameters C$\text{}_{W}$(x) of the gas mixture CH$\text{}_{3}$CN+OCS and CH$\text{}_{3}$CN+H$\text{}_{2}$ are 14.05±0.30 MHz/Tr, 9.15±0.12 MHz/Tr, respectively and the temperature dependence parameters α are -0.90 ± 0.07 and -0.77 ± 0.08

Pressure Broadening of J=1 ← 0 Rotational Line of Fluoroform Caused by Spherical Perturbers

The foreign-gas broadening parameter was measured for CHF$\text{}_{3}$ molecule interacting with spherical (SF$\text{}_{6}$, CF$\text{}_{4}$, CH$\text{}_{4}$, CCl$\text{}_{4}$) perturbers and the pressure shift parameter of rotational transition J=1 ← 0 in the CHF$\text{}_{3}$ molecule was obtained. For the systems of trifluoromethane molecule and four spherical molecules as perturbers the collision cross-sections were determined. Experimental line width parameters are interpreted using Anderson-Tsao-Curnutte as well as Murphy-Boggs theories. Accounting for the dispersive and inductive interactions the cross-section was determined. The theoretical values are in qualitative agreement with the experimental results, but the absolute values of the measured cross-section were larger than these calculated