Reactivity of the Bicyclic Amido‐Substituted Silicon (I) Ring Compound Si 4 {N(SiMe 3 )Mes} 4 with FLP‐Type Character

We introduce the definition of the typical irreducible modules of the generalized quantum groups, and prove the Weyl–Kac-type formulas of their characters. As a by-product, we obtain the Weyl–Kac-type character formulas of the typical irreducible modules of the quantum superalgebras associated with the basic classical Lie superalgebras, which is explained in Introduction.

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Synchrotron spectroscopy of the CSH-bending and CH3-rocking bands of methyl mercaptan

Canadian Journal of Physics ◽

10.1139/cjp-2019-0487 ◽

2020 ◽

Vol 98 (6) ◽

pp. 519-529

Author(s):

R.M. Lees ◽

E.M Reid ◽

Li-Hong Xu ◽

B.E. Billinghurst

Keyword(s):

Ground State ◽

Vibrational Mode ◽

Good Representation ◽

Methyl Mercaptan ◽

Vibrational Modes ◽

Oscillatory Structure ◽

Out Of Plane ◽

Type Character ◽

Fourier Transform Spectra ◽

Synchrotron Spectroscopy

The CSH-bending and CH3-rocking infrared bands of CH3SH have been investigated in Fourier transform spectra recorded at 0.001 cm−1 resolution employing synchrotron radiation at the Canadian Light Source in Saskatoon. The relative band strengths and structures are quite different from those of the CH3OH methanol analogue, with the CSH bend being very weak and both the in-plane and out-of-plane CH3 rocks being strong with intensities greater than the C–S stretch. The CSH bend has parallel a-type character with no detectable b-type component. The out-of-plane CH3 rock is a purely c-type perpendicular band, whereas the in-plane rock is of mixed a/b character. Sub-bands have been assigned for A and E torsional species up to about K = 10 for each vibrational mode, providing upper-state term values from which K-reduced substate origins were determined. For the CSH bend, the origins follow the customary oscillatory torsional pattern as a function of K with a sharply reduced amplitude of 0.362 cm−1 compared to the 0.653 cm−1 for the ground state. The torsional energy curves for the out-of-plane rock are also well-behaved but have inverted ordering of the A–E torsional splitting components and a larger amplitude of 1.33 cm−1. In contrast, the substate origins for the in-plane rock are scattered over a range of about 2 cm−1 without clear oscillatory structure. Several instances of coupling among the lower modes and the ground state via resonances between accidentally near-degenerate levels have been observed and characterized. Ab initio calculations are found to give a good representation of the frequency and relative intensity patterns for the lower vibrational modes.

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Late Permian – Triassic Granitic Magmatism of western part of the Northern Taimyr: evidence for two magmatic events.

10.5194/egusphere-egu2020-12752 ◽

2020 ◽

Author(s):

Mikhail Kurapov ◽

Victoria Ershova ◽

Andrey Khudoley ◽

Aleksandr Makariev ◽

Elena Makarieva

Keyword(s):

Alkali Feldspar ◽

Coarse Grained ◽

Late Triassic ◽

Taimyr Peninsula ◽

Early Triassic ◽

Late Permian ◽

Lower Paleozoic ◽

Metasedimentary Rocks ◽

Peraluminous Granites ◽

Type Character

The studied intrusions are located within the Northern Taimyr domain (southern part of the Kara terrane) on the northwestern coast of the Taimyr Peninsula and on several islands in Kara Sea. Intrusions cut the Lower Paleozoic metasedimentary rocks.Late Permian &#8211; Early Triassic intrusions are represented by coarse- to medium-grained quartz-syenites and alkali-feldspar-granites. U-Pb dating of these granites yelled age of 253 Ma. Ar-Ar micas ages varies from 236 to 251 Ma. The granites are high- to medium acidic, high alkaline (alkali-calcic to alkalic), ferroan and magnesian, mainly peraluminous. Granites are characterized by relatively low initial 87Sr/86Sr ratio (0.7041) and slightly positive &#949;Nd(t) value (1.03).Middle &#8211; Late Triassic intrusions are represented by coarse-grained granodiorites and granites. U-Pb zircon ages of these granites range from 228 to 238 Ma. Ar-Ar micas and amphibole ages varies from 206 to 235 Ma. They are acidic to low acidic, moderately alkaline (alkali-calcic, calc-alkalic), magnesian, peraluminous and metaluminous. Middle &#8211; Late Triassic granites are characterized by higher initial 87Sr/86Sr ratios (0.7045-0.7060) and negative &#949;Nd(t) values (-5.47 to -0.80).Late Permian &#8211; Early Triassic high alkalic predominantly ferroan granites are most likely related to A-type granites. Middle &#8211; Late Triassic moderate alkalic magnesian granites have transitional I/S-type character. Thus, Late Permian &#8211; Early Triassic granites likely form an outer rim of the Permo-Triassic Siberian plume. Middle &#8211; Late Triassic granites of Northern Taimyr were formed from different source with more significant crustal component contribution. Obtained data suggests two magmatic events throughout Early Mesozoic that affected Northern Taimyr.This research was supported by RFBR project No. 19-35-90006

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Fourier transform spectroscopy of the OD-bending band of CH3OD

Canadian Journal of Physics ◽

10.1139/cjp-2012-0521 ◽

2013 ◽

Vol 91 (11) ◽

pp. 949-956 ◽

Cited By ~ 3

Author(s):

R.M. Lees ◽

Li-Hong Xu ◽

B.E. Billinghurst

Keyword(s):

Fourier Transform ◽

Energy Structure ◽

A Value ◽

Small Admixture ◽

Power Series Expansions ◽

Type Character ◽

Character Plus ◽

Fourier Transform Spectrum ◽

Fourier Model ◽

Rotation Energy

The infrared Fourier transform spectrum of the OD-bending fundamental band of the CH3OD isotopologue of methanol has been investigated and analyzed in the 745–945 cm−1 region. The OD-bend is of hybrid a–b type, with predominantly parallel a-type character plus a small admixture of perpendicular b-type structure. The K-structure in the central Q-branch region is unusually well resolved and shows substantial shading to higher wavenumber. Sub-bands have been assigned for the vt = 0 ground torsional state from K = 0 to 13 for both A and E torsional species, as well as a number of sub-bands in the vt = 1, 2 excited torsional states. Upper-state term values have been determined from the observations and fitted to J(J + 1) power-series expansions to explore the torsion–K-rotation energy structure of the excited OD-bending state. A simple Fourier model for the energy structure gives a wavenumber of 863.246 cm−1 for the vt = 0 origin of the OD-bending band. The K = 0 torsional (E − A) splitting of 2.456 cm−1 found for the vt = 0 OD bend is 5.6% smaller than that of the ground state, and would correspond to a 9.9 cm−1 increase in the torsional barrier height, V3, to a value of approximately 376.2 cm−1 if other parameters do not change.

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