1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Gyroscopic destabilisation in polyatomic molecules: Rotational structure of the low-frequency bending vibrational states ν23 and ν11 of dimethylsulfoxide
Rent:
Rent this article for
USD
10.1063/1.4809738
/content/aip/journal/jcp/138/23/10.1063/1.4809738
http://aip.metastore.ingenta.com/content/aip/journal/jcp/138/23/10.1063/1.4809738

Figures

Image of FIG. 1.
FIG. 1.

Schematic representation of the equilibrium configuration of (CH)SO (DMSO) according to computations; the three principal axes of inertia cross at the center of mass, axes and (vertical) lie in the symmetry plane. Reproduced with permission from A. Cuisset, L. Nanobashvili, I. Smirnova, R. Bocquet, F. Hindle, G. Mouret, O. Pirali, P. Roy, and D. A. Sadovskií, Chem. Phys. Lett.492, 30 (Year: 2010)10.1016/j.cplett.2010.04.042. Copyright 2010, Elsevier B.V. A. Cuisset, O. Pirali, and D. A. Sadovskií, Phys. Rev. Lett.109, 094101 (Year: 2012)10.1103/PhysRevLett.109.094101. Copyright 2012, American Physical Society.

Image of FIG. 2.
FIG. 2.

Spectrum (lower trace, blue) of the ν and ν fundamental bands of DMSO observed using the AILES beamline of the synchrotron ( = 0.06 Torr, = 150 m, Δν = 0.00015 cm, 700 scans, 46 h of acquisition) by Cuisset , and predicted transitions (stick spectrum, upper trace, black). The amplitude scaling of the two traces is independent; the experimental unresolved ν -branch takes nearly the full height of the plot. The insets (top) represent the lowest vibrational energy levels of DMSO in cm according to our measurements for ν and ν and the harmonic frequencies computed by . Gray lines represent dipole inactive states and their overtones, arrows show the transitions analyzed in this work.

Image of FIG. 3.
FIG. 3.

Classical rotational energy of DMSO in the ν fundamental vibrational excited state (a) and the ground state (b) with angular momentum = 50. The surfaces are drawn in slightly rotated coordinates ( , , ) of Fig. 1 . In both plots, the energy is given, up to the same fixed additive constant and scale, by the radial distance from the origin as function of the position of the instantaneous axis of rotation. Equidistant sets of constant energy are stripe painted to display more clearly the shape of the surfaces. We see a deep minimum along the axis (vertical) and very shallow height variations in the equatorial area. The animation shown in DMSOsRE-animj.gif of the supplementary material illustrates the evolution of the rotational energy of ν as varies on the interval [30, 60]. Adapted from Ref. .

Image of FIG. 4.
FIG. 4.

Absorption spectrum of the ν and ν fundamentals of DMSO in the rigid symmetric top approximation at 298 K. Different branches of the perpendicular band 0 → ν and parallel and perpendicular components of the 0 → ν band are color coded.

Image of FIG. 5.
FIG. 5.

Reciprocal multiplets (35) and (33) of the 0 → ν spectrum. Gray line shows the observed FT-FIR spectrum; blue and orange sticks mark computed intensities for dipole moment components μ (dominant ‖ component) and μ (⊥ component); or assignments for most prominent lines are displayed on top of the sticks in blue or brown, respectively. Note that the presence of many weaker lines of other bands obscures the μ-transitions in this region.

Image of FIG. 6.
FIG. 6.

The μ multiplet (7) and the neighboring μ transitions () with = 10…12 and = , − 1, … in the 0 → ν spectrum. The observed FT-FIR spectrum is shown by gray solid line; blue and orange sticks mark computed intensities for dipole moments μ (‖ component) and μ (⊥ component). For the (7) lines, their or assignments are displayed on top of the blue sticks in blue or brown, respectively; for the () lines, the assignments are given in red on top of the orange sticks.

Image of FIG. 7.
FIG. 7.

Errors (theory–experiment) in reproducing rotational transitions in the ν FIR band. Red and blue represent and -type levels, respectively.

Image of FIG. 8.
FIG. 8.

Rotational structure of the vibrational state ν of DMSO reconstructed using parameters in Table I . Energies (level dashes) are shown after subtracting the average classical ground state rotational energy ; observed levels are marked by longer dashes; bold solid lines represent energies of classical stationary axes of rotation (relative equilibria), the neighboring state ν is indicated in gray. A dashed line marks locally perturbed ν levels with = 15–16 and = 30…40.

Image of FIG. 9.
FIG. 9.

Errors (theory–experiment) in reproducing rotational transitions in the (35) sub-branch of 0 → ν exhibiting a local perturbation of ν near = 15–16 for = 34.

Image of FIG. 10.
FIG. 10.

Assignment of the reciprocal and sub-branches in the 0 → ν spectrum, see Sec. ??? . (a) Quasi-linear dependence of Q and Q sub-branch heads on := . (b) Reduced frequency plot (Loomis-Wood diagram) of Q sub-branch lines. (c) Centered reduced frequencies of Q() sub-branch lines with = 11. (d) Errors in the combination differences for Q() and Q(J) with = 11.

Image of FIG. 11.
FIG. 11.

Reciprocal multiplets () and () with = 11 in the 0 → ν spectrum, cf. Fig. 10(a) . Gray line shows the observed FT-FIR spectrum; sticks mark computed intensities for the dipole moment μ (⊥ component); assignments are displayed on top of the sticks.

Image of FIG. 12.
FIG. 12.

Errors (theory–experiment) in reproducing rotational transitions in the ν FIR band. Red and blue represent and -type levels, respectively.

Image of FIG. 13.
FIG. 13.

Rotational structure of the vibrational state ν of DMSO reconstructed using parameters in Table I . Energies (horizontal dashes) are shown after subtracting the average classical ground state rotational energy ; observed levels are marked by longer dashes; bold solid lines represent energies of classical stationary axes of rotation (relative equilibria), the neighboring state ν is indicated in gray.

Image of FIG. 14.
FIG. 14.

Upper part of the rotational multiplet of the ν fundamental vibrational state of DMSO, cf. Fig. 13 . Energies are shown after subtracting the classical energy of rotation about the unstable stationary axis . Horizontal dashes mark quantum levels; bold solid lines represent energies of classical stationary rotations, the levels of the neighboring state ν are indicated in gray. Circles mark level sequences engaged in the -type quadruplet formation. Reproduced by permission from A. Cuisset, O. Pirali, and D. A. Sadovskií, Phys. Rev. Lett.109, 094101 (Year: 2012)10.1103/PhysRevLett.109.094101. Copyright 2012, American Physical Society.

Image of FIG. 15.
FIG. 15.

Latitudinal tilt φ (degrees) of new axes of stationary rotation in the ν state of DMSO, cf. Fig. 3(a) .

Tables

Generic image for table
Table I.

Vibration-rotation parameters (MHz) of the effective Hamiltonian of DMSO in the model of isolated vibrational states; the value of a parameter for the vibrational state ν equals the sum of values in columns |0⟩ and ν, e.g., . Parameters of the ground state fixed to zero.

Generic image for table
Table II.

Summary of the analysis of the spectroscopic data for DMSO used in our work: For each band, we give the total number of assigned lines, the values of the total angular momentum , the estimated unweighted σ and weighted σ standard errors of the fit, and the number of assigned lines with errors above ±2σ.

Generic image for table
Table III.

Frequencies (cm) and observed–calculated errors (Err.) (10 cm) of the assigned lines in the far IR ν ← 0 spectrum of DMSO, which involve the quadruple rotational states of type of the fundamental vibrational excited state ν.

Generic image for table
Table IV.

Comparison of experimental and estimated frequencies (cm) of bending vibrational modes of DMSO; G-h and G-a refer to harmonic and anharmonic frequencies computed using , see Appendix A of the supplementary material. The experimental frequencies of ν and ν are obtained from the intensities of the respective MW satellite bands relative to those in the 0 ← 0 band; the ν frequency comes from the liquid state Raman spectrum.

Loading

Article metrics loading...

/content/aip/journal/jcp/138/23/10.1063/1.4809738
2013-06-18
2014-04-20
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Gyroscopic destabilisation in polyatomic molecules: Rotational structure of the low-frequency bending vibrational states ν23 and ν11 of dimethylsulfoxide
http://aip.metastore.ingenta.com/content/aip/journal/jcp/138/23/10.1063/1.4809738
10.1063/1.4809738
SEARCH_EXPAND_ITEM