Trends in field desorption mass spectra of several series of alkali metal cryptates: thermodynamic rationale and analytical implications

1980 ◽  
Vol 58 (7) ◽  
pp. 681-685 ◽  
Author(s):  
Gordon Walter Wood ◽  
Mei-Kuen Au ◽  
Ning Mak ◽  
Pui-Yan Lau
Keyword(s):  
Alkali Metal ◽  
Thermodynamic Parameters ◽  
Mass Spectra ◽  
Goodness Of Fit ◽  
Metal Cations ◽  
Complex Stability ◽  
Field Desorption ◽  
Alkali Metal Cations ◽  
The Stability ◽  
Almost All

Field desorption mass spectra have been recorded for most of the 45 cryptates which may be formed from complexation of [2.2.2]-, [2.2.1]-, and [2.1.1]-cryptand with Li+, Na+, an d K+ ions in combination with the anions Cl−, Br−, I−, OTs−, and BPh4−. The cryptate cation predominated in almost all of the spectra. The stability of the complexes was found not to be simply related to goodness of fit of the cation in the cryptand cavity, but a significant trend in stability in the order BPh4 > 1 > Br > Cl was found. This order of complex stability was shown to be consistent with known thermodynamic parameters. These results are discussed briefly in terms of applications to analysis of alkali metal cations.

Mass Spectrometric Behaviour of Carboxylated Polyethylene Glycols and Carboxylated Octylphenol Ethoxylates

2003 ◽  
Vol 9 (3) ◽  
pp. 165-173 ◽  
Author(s):  
Magdalena Frańska ◽  
Agnieszka Zgoła ◽  
Joanna Rychłowska ◽  
Andrzej Szymański ◽  
Zenon Łukaszewski ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Alkali Metal ◽  
Mass Spectra ◽  
Secondary Ion Mass Spectrometry ◽  
Metal Cations ◽  
Mass Spectrometric ◽  
Polyethylene Glycols ◽  
Alkali Metal Cations ◽  
Secondary Ion

The mass spectrometric behaviour of mono- and di-carboxylated polyethylene glycols (PEGCs and CPEGCs) and carboxylated octylphenol ethoxylates (OPECs) is discussed. The tendency for ionisation (deprotonation, protonation and cationisation by alkali–metal cations) of carboxylated PEGs was compared with that of non-carboxylated analogues by using both secondary-ion mass spectrometry (SIMS) and electrospray ionisation (ESI). The fragmentation of the PEGCs and CPEGCs is discussed and also compared with their neutral analogues, PEGs. B/E linked-scan mass spectra were recorded, using secondary-ion mass spectrometry as a method for ion generation, for deprotonated and protonated molecules as well as for molecules cationised by alkali–metal cations. The fragmentation behaviour of PEGs is found to be different from that of CPEGCs, The presence of carboxyl groups may be confirmed not only by the determination of molecular weights of the ethoxylates studied, but also on the basis of the fragment ions formed. The metastable decomposition of the [OPEC-H]− ions proceeds through the cleavage of the bond between the octylphenol moiety and the ethoxylene chain and leads to the octylphenoxyl anions. It permits determination of the mass of the hydrophobic moiety of the studied carboxylated alkylphenol ethoxylate. ESI mass spectra recorded in the negative-ion mode were found to be more suitable than SI mass spectra for the determination of the average molecular weight of carboxylated ethoxylates.

scholarly journals The phenoxyl group-modulated interplay of cation–π and σ-type interactions in the alkali metal series

2020 ◽  
Vol 22 (46) ◽  
pp. 27105-27120
Author(s):  
Giacomo Prampolini ◽  
Marco d'Ischia ◽  
Alessandro Ferretti
Keyword(s):  
Alkali Metal ◽  
Noncovalent Interactions ◽  
Metal Cations ◽  
Alkali Metal Cations ◽  
Striking Effect

An extensive exploration of the interaction PESs of phenol and catechol complexes with alkali metal cations reveals a striking effect of –OH substitution on the balance between cation-π and σ-type noncovalent interactions.

Influence of Alkali Metal Cations on the Photodimerization of Bromo Cinnamates Studied by Solid-State NMR

2020 ◽  
Vol 124 (50) ◽  
pp. 27614-27620
Author(s):  
Marufa Zahan ◽  
He Sun ◽  
Sophia E. Hayes ◽  
Harald Krautscheid ◽  
Jürgen Haase ◽  
...  
Keyword(s):  
Solid State ◽  
Alkali Metal ◽  
Solid State Nmr ◽  
Metal Cations ◽  
Alkali Metal Cations

Derivation of Class II Force Fields. 4. van der Waals Parameters of Alkali Metal Cations and Halide Anions

1997 ◽  
Vol 101 (39) ◽  
pp. 7243-7252 ◽  
Author(s):  
Zhengwei Peng ◽  
Carl S. Ewig ◽  
Ming-Jing Hwang ◽  
Marvin Waldman ◽  
Arnold T. Hagler
Keyword(s):  
Alkali Metal ◽  
Force Fields ◽  
Van Der Waals ◽  
Metal Cations ◽  
Class Ii ◽  
Alkali Metal Cations ◽  
Halide Anions

Fluorescence enhancement of dibenzo-18-crown-6 by alkali metal cations

1980 ◽  
Vol 84 (9) ◽  
pp. 994-999 ◽  
Author(s):  
Haruo Shizuka ◽  
Kiyoshi Takada ◽  
Toshifumi Morita
Keyword(s):  
Alkali Metal ◽  
Fluorescence Enhancement ◽  
Metal Cations ◽  
Alkali Metal Cations
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