The efficient production of polyprotonated oligonucleotides, studied at n ≤ 19, occurs from water/propan-2-ol solutions over an ammonium acetate concentration range between 2.5 and 40 mM and a pH range from 5 to 11. Average charge-state levels observed were approximately half of those found in mass
Vibrational relaxation and collision-induced dissociation of xenon fluoride by neon
✍ Scribed by Roger L. Wilkins
- Publisher
- John Wiley and Sons
- Year
- 1989
- Tongue
- English
- Weight
- 590 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0538-8066
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✦ Synopsis
Rate coefficients were calculated for vibrational relaxation and collision-induced dissociation of ground state xenon fluoride in neon a t temperatures between 300 and 1000 K for each of nine vibrational levels. These coefficients were calculated using a pairwise additive potential energy surface, which consists of a Morse function for the XeF interaction and Lennard-Jones functions for the NeXe and NeF interactions. Rate coefficients are provided for both temperature and u-dependences. The vibrational relaxation and dissociation processes occur by multiquanta transitions. Dissociation can take place from all u-Ievels provided that the internal energy of the XeF molecule is close to the rotationless dissociation limit. The order of increase effectiveness of the various forms of energy in promoting dissociation in XeF was found to be translationrotation-vibration. At room temperature, neon atoms were found to be more efficient than helium atoms in the dissociation processes; helium atoms were found to be more efficient than neon atoms in the vibrational relaxation of XeF. Strong vibration-rotation coupling in both vibrational relaxation and in the dissociation processes is demonstrated.
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