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Reetz, Manfred T.; Hütte, Stephan; Goddard, Richard

doi:10.1002/(sici)1521-3897(199904)341:3<297::aid-prac297>3.3.co;2-j

Cited by 6 publications

(8 citation statements)

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“…a higher contribution of 7 than 4 to the structure), giving both a higher nitrile nitrogen electronic density and a lower CN bond order. In this connection we note that the CN stretching frequency (2104cm À1 ) of Bu 3 N N À CN is very close to that (2080 cm À1 ) of the carbanion in the dimer 31 [Bu 4 N , Ph(Me)C À CN] 2 .…”

Section: Infrared Group Frequenciessupporting

confidence: 56%

R3N+N?: a substituent with extreme electronic effects

Illien

Berthelot

Morris

et al. 2000

J. Phys. Org. Chem.

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Basicity, infrared and x‐ray results are reported which show the uniquely high electron‐donor effect of R3N+N− substituents. An explanation is offered in terms of theoretically calculated resonance, field and electronegativity σ substituent constants. Large values of the calculated first‐order hyperpolarizabilities in the R3N+N−(CHCH) nNO2 series suggest the introduction of the R3N+N− substituents in the synthesis of push–pull conjugated structures for second‐order non‐linear optics. Copyright © 2000 John Wiley & Sons, Ltd.

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Section: Infrared Group Frequenciessupporting

confidence: 56%

R3N+N?: a substituent with extreme electronic effects

Illien

Berthelot

Morris

et al. 2000

J. Phys. Org. Chem.

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“…This view is strongly supported by the X-ray molecular structure of the Bu 4 N + salt of 1-cyano-1-phenylethanide, prepared by the treatment of 2 (X = H) with Bu 4 NOH. 11 The essential planarity of the anion, coupled with the finding that only the nitrogen of the cyano group is involved in multiple hydrogen bonding interactions with the α-methylene groups of the cations, is indicative of very little delocalization of the negative charge to the sp 2 benzylic carbon atom, as well as significant delocalization to the nitrogen atom of the cyano group. In our case, a high negative charge density on the nitrogen atom of the CN group would guarantee a strong electrostatic stabilization of B′′ , whose shape is supposed to be one in which the group C N – points to the proton embedded in the two-phenanthroline core.…”

Section: Resultsmentioning

confidence: 99%

Variations in the fuel structure control the rate of the back and forth motions of a chemically fuelled molecular switch

et al. 2018

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“…The lithium abundances are determined using the spectral synthesis method with the IDL/Fortran SIU software package developed by Reetz (1993). The synthetic spectrum is represented by a single Gaussian profile, with the combined broadening effects of stellar rotation, macroturbulence and the instrument profile.…”

Section: Discussionmentioning

confidence: 99%

The Lithium Abundances of a Large Sample of Red Giants

Liu

Tan

Wang

et al. 2014

ApJ

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The lithium abundances for 378 G/K giants are derived with non-LTE correction considered. Among these, there are 23 stars that host planetary systems. The lithium abundance is investigated, as a function of metallicity, effective temperature, and rotational velocity, as well as the impact of a giant planet on G/K giants. The results show that the lithium abundance is a function of metallicity and effective temperature. The lithium abundance has no correlation with rotational velocity at vsini < 10 km s −1 . Giants with planets present lower lithium abundance and slow rotational velocity (vsini < 4 km s −1 ). Our sample includes three Li-rich G/K giants, 36 Li-normal stars and 339 Li-depleted stars. The fraction of Li-rich stars in this sample agrees with the general rate of less than 1% in literature, and the stars that show normal amounts of Li are supposed to possess the same abundance at the current interstellar medium. For the Lidepleted giants, Li deficiency may have already taken place at the main sequence stage for many intermediate-mass (1.5-5 M ⊙ ) G/K giants. Finally, we present the lithium abundance and kinematic parameters for an enlarged sample of 565 giants using a compilation of literature, and confirm that the lithium abundance is a function of metallicity and effective temperature. With the enlarged sample, we investigate the differences between the lithium abundance in thin-/thick-disk giants, which indicate that the lithium abundance in thick-disk giants is more depleted than that in thin-disk giants.

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Cited by 6 publications

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R3N+N?: a substituent with extreme electronic effects

R3N+N?: a substituent with extreme electronic effects

Variations in the fuel structure control the rate of the back and forth motions of a chemically fuelled molecular switch

The Lithium Abundances of a Large Sample of Red Giants

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