Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.596544
Title: Novel phosphorus-bearing transient molecules studied by infrared diode laser spectroscopy
Author: Bell, I. S.
Awarding Body: University of Cambridge
Current Institution: University of Cambridge
Date of Award: 1999
Availability of Full Text:
Full text unavailable from EThOS. Please contact the current institution’s library for further details.
Abstract:
Studies of the reaction of white phosphorus vapour with oxygen are of considerable fundamental and practical interest. The reaction produces an intense chemiluminescence, although the identity of the emitting species has been controversial. In the experiments reported in this thesis, the phosphorus glow has been probed directly using infrared diode laser absorption spectroscopy to detect some of the transient intermediates present. The introductory chapter presents a review of the advantages of using lasers over conventional sources as spectroscopic tools. Lasers output light of a monochromatic nature, enabling extremely high resolution measurements to be made, whilst their high power engenders excellent sensitivity. The development of tunable infrared sources, especially the semiconductor diode laser, is also described. A review of previous spectroscopic measurements of transient phosphorus-bearing species is then presented, along with a discussion of some of the applications associated with their observation. A diode laser spectrometer equipped with a multi-pass (White) cell has been used to study such short-lived species in the experiments reported in this thesis, and is described in chapter 2. The transient species PO and PO2 have previously been observed in this laboratory. Chapter 3 presents the first reliable rotational assignment of P2O molecule, observed in the reaction of oxygen atoms with white phosphorus vapour. The addition of NO to this reaction mixture was then found to produce PNO, another analogue of N2O, as described in chapter 4. The upper state of the N=O stretching fundamental of the PNO molecule was found to be perturbed, enabling an absolute assignment of the infrared spectrum of this band to be made. This reaction opens the door to a range of novel species that may be produced in this system. The next two chapters describe the addition of halogen molecules to the phosphorus glow, producing the ClPO and BrPO molecules. Their infrared spectra have been assigned with the aid of a Loomis-Wood spectral display program.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.596544  DOI: Not available
Share: