scholarly journals Mixed-field orientation of molecules without rotational symmetry

2013 ◽  
Vol 139 (23) ◽  
pp. 234313 ◽  
Author(s):  
Jonas L. Hansen ◽  
Juan J. Omiste ◽  
Jens H. Nielsen ◽  
Dominik Pentlehner ◽  
Jochen Küpper ◽  
...  
Keyword(s):  
Rotational Symmetry ◽  
Field Orientation ◽  
Mixed Field ◽  
Orientation Of Molecules

scholarly journals Theoretical description of adiabatic laser alignment and mixed-field orientation: the need for a non-adiabatic model

2011 ◽  
Vol 13 (42) ◽  
pp. 18815 ◽  
Author(s):  
J. J. Omiste ◽  
M. Gärttner ◽  
P. Schmelcher ◽  
R. González-Férez ◽  
L. Holmegaard ◽  
...  
Keyword(s):  
Theoretical Description ◽  
Field Orientation ◽  
Laser Alignment ◽  
Mixed Field

Non-adiabatic effects in near-adiabatic mixed-field orientation and alignment

2016 ◽  
Vol 479 ◽  
pp. 63-71 ◽  
Author(s):  
Anjali Maan ◽  
Dharamvir Singh Ahlawat ◽  
Vinod Prasad
Keyword(s):  
Field Orientation ◽  
Mixed Field

scholarly journals Adiabatic Mixed-Field Orientation of Ground-State-Selected Carbonyl Sulfide Molecules

ChemPhysChem ◽  
2016 ◽  
Vol 17 (22) ◽  
pp. 3740-3746 ◽  
Author(s):  
Jens S. Kienitz ◽  
Sebastian Trippel ◽  
Terry Mullins ◽  
Karol Długołęcki ◽  
Rosario González-Férez ◽  
...  
Keyword(s):  
Ground State ◽  
Carbonyl Sulfide ◽  
Field Orientation ◽  
Mixed Field

Structure Determination for the Crystalline Phase of Triphenyl Phosphite by Means of Multi-Dimensional Solid-State NMR and X-Ray Diffraction

2001 ◽  
Vol 56 (11) ◽  
pp. 1089-1099 ◽  
Author(s):  
Jürgen Senker ◽  
Jens Lüdecke
Keyword(s):  
Solid State ◽  
Structure Determination ◽  
Crystalline Phase ◽  
Solid State Nmr ◽  
Spin Diffusion ◽  
Rotational Symmetry ◽  
Triphenyl Phosphite ◽  
X Ray Diffraction ◽  
X Ray ◽  
Orientation Of Molecules

The crystalline phase of triphenyl phosphite P(OC6H5)3 was investigated by means of 31P solid-state NMR and X-ray diffraction in a temperature range between 170 K and its melting point (Tm = 293 K). ID MAS NMR spectra exhibit one sharp central resonance indicating only one crystallographically unique molecule in the unit cell. A theoretical analysis concerning the shape of 2D exchange spectra for 1 = 1 /2 nuclei is presented. It is shown that if the exchange is caused by radio-frequency driven spin-diffusion, this technique allows to discriminate rotational symmetry elements in crystalline solids. Used on crystalline triphenyl phosphite, 3-fold symmetry could be revealed clearly. Structure determination based on X-ray single crystal diffraction data collected at 191 K shows that triphenyl phosphite crystallises in hexagonal metric with space group R3̅(wR2= 8.3%, Z = 18) and one molecule in the asymmetric unit. This result is in excellent agreement with the NMR spectroscopic data. The lattice parameters at 200 K were determined to a = 37.887(1) and c = 5.7567(2) Å (V = 7156(1) Å3) by refining an X- ray powder-diffraction pattern. The structure of triphenylphosphite can be described as a close rod packing. The rods are formed by ecliptically arranged triphenylphosphite molecules. Due to the 3-fold rotoinversion axis the orientation of molecules in neighboured rods is antiparallel.

Comparison of Calculated and Recorded Electron Energy-Loss Spectra of Aluminium and Carbon

1990 ◽  
Vol 48 (2) ◽  
pp. 64-65
Author(s):  
L. Reimer ◽  
R. Oelgeklaus
Keyword(s):  
Fourier Transform ◽  
Energy Loss ◽  
Electron Energy ◽  
Rotational Symmetry ◽  
Mean Free Path ◽  
Single Scattering ◽  
Specimen Thickness ◽  
Two Dimensional ◽  
Image Position ◽  
Electron Energy Loss

Quantitative electron energy-loss spectroscopy (EELS) needs a correction for the limited collection aperture α and a deconvolution of recorded spectra for eliminating the influence of multiple inelastic scattering. Reversely, it is of interest to calculate the influence of multiple scattering on EELS. The distribution f(w,θ,z) of scattered electrons as a function of energy loss w, scattering angle θ and reduced specimen thickness z=t/Λ (Λ=total mean-free-path) can either be recorded by angular-resolved EELS or calculated by a convolution of a normalized single-scattering function ϕ(w,θ). For rotational symmetry in angle (amorphous or polycrystalline specimens) this can be realised by the following sequence of operations :(1)where the two-dimensional distribution in angle is reduced to a one-dimensional function by a projection P, T is a two-dimensional Fourier transform in angle θ and energy loss w and the exponent -1 indicates a deprojection and inverse Fourier transform, respectively.

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