Unusual spectroscopic properties of CF3H dissolved in liquified Ar, N2, CO, and CO2

Car–Parrinello Molecular Dynamics Study of a Blue‐Shifted Intermolecular Weak‐Hydrogen‐Bond System

“…Table 3 lists the frequencies derived from the CPMD simulations by using the velocity-velocity and the dipole-moment autocorrelation functions. For comparison we also show the experimental frequencies for fluoroform in the gas phase [30][31] and in carbon monoxide solution [22] at 100 K. The CPMD simulation correctly predicts the blue shift Dñ 1 (+ 27 cm À1 ), albeit overestimated by 10 cm À1 in comparison to experiment. Also the intensity of the peak attributed to this band decreases in qualitative agreement with experiment.…”

“…We simulated a system consisting of a single fluoroform molecule and 26 carbon monoxide molecules in a cubic cell of side a = 11.2 with periodic boundary conditions at a temperature of 100 K. The concentration of fluroroform, the density of the solution, and the temperature were set up according to the experimental conditions. [22] A simulation of a single fluoroform molecule in vacuum was performed under the same conditions in a box of the same size. We used pseudopotentials in the form proposed by Hartwigsen et al [46] with a plane-wave energy cutoff of 60 Ry.…”

“…Experimental FTIR data [22] Theoretical results (CPMD) (Symmetry) F 3 CH, gas phase F 3 CH in liquid CO, 100 K F 3 CH, gas phase F 3 CH in liquid CO, 100 K bond length is on the order of 1.2 , a peak corresponding to the carbon atom in this F 3 CH···OC complex can be found in Figure 2 in the region R(H···C) = 3.3-3.7 , a(CÀH···C) = 100-1108.…”

“…[29] This system involving weak blue-shifted H-bond interactions was recently investigated experimentally in detail by FTIR spectroscopy. [22] The Car-Parrinello method allows us to follow the dynamics of complex formation and breaking with interactions described at the density functional theory (DFT) level. The stoichiometry of the different complexes and their residence time can be naturally derived.…”

Car–Parrinello Molecular Dynamics Study of the Blue‐Shifted F3CH⋅⋅⋅FCD3System in Liquid N2

“…In general, the systems studied in the liquid phase can be divided into two groups: one where the blue-shifted complex AÀH···B is dissolved in weakly interacting liquefied rare gases, [12,13,16,19,38] and the other where the proton donor molecules are dissolved in molecular solvents, often acting as proton acceptors. [14,18,21] Usually the effect of liquefied rare gases on the spectroscopic parameters of the vibrational bands of interest is considered to be of secondary importance. In such a case, a theoretical analysis based on static ab initio calculations results in reasonable conclusions and truly reflects the experimental observations.…”