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Review of laser enhanced ionisation spectroscopy
Book
The authors are to be congratulated on making a notable contribution to the advancement of the subject and I strongly recommend the volume as unique in its coverage and as a useful buy to all individuals and departments with a substantial interest in vibrational spectroscopy. D. C. McKean
Chemistry Department University of Edinburgh Edinburgh UK PI1 Sl386-1425(97)00128-5
Review of Laser Enhanced Ionisation Spectroscopy John C. Travis and Gregory C. Turk,
John Wiley and Sons, ISBN 0 471 576840,&60.00. The key to whether or not one is likely to find this a useful volume may be found in the Preface. The editors explain that a more accurate, if cumbersome title would have been Laser Enhanced Collisional Ionisation Spectroscopy. The Laser Enhanced Ionisation (LEI) to be described is familiar to most spectroscopists in the form of optogalvanic spectroscopy. This book is not therefore primarily concerned with REMPI, LIF or any other members of the alphabet soup that go to make up the collection of techniques employing lasers as ionisation sources. Bearing that restriction in mind this book provides a most useful introduction to the topic of LEI, focusing on the fundamentals, rather than applications. The first two chapters, which occupy approximately half of the book, provide detailed model calculations of ion generation and detection respectively. A simplified kinetic scheme is introduced to describe the ionisation process. It is employed to provide a number of key equations that will aid in the choice of experimental conditions. For example, what is the optimum beam size or excitation wavelength; should one or two colour, pulsed or continuous excitation be employed? The chapter concludes with a density matrix treatment of ion generation, which permits the extension to the cases where Stark broadening
reviews
3191
or direct two photon excitation is important. The chapter on signal detection employs an electrostatic model to calculate the charge transport and current generation following ionisation. A number of practical issues are addressed, and the model is incorporated into a (quick basic) program, which is included as an appendix. The analytical performance of LEI is considered in the third chapter, which contains a rather detailed description of experimental apparatus. There is some overlap between this chapter and those which precede it. A useful table on the experimentally determined detection limit for a number of elements is included. The next chapter contains a bibliography of the application of LEI in flames, while Chapter 5 introduces some non-flame (furnace, plasma, etc.) media. The final chapter describes some more elaborate ionisation schemes which make use of simultaneous measurements of ions and fluorescence. The additional information is interesting, but the more complex nature of the experiments raised some doubts about their analytical uses. Overall this is a well-produced and well-written contribution to the series, containing few errors and a consistent style between chapters. It is. especially in the first two chapters, likely to be of great use to anyone with an interest in the application of lasers in analytical chemistry. This volume is then likely to find a useful place in many chemistry and analytical libraries. S. Meech School of Chemical Sciences University of East Anglia Norwich UK PIZ S1386-1425(97)00129-7
Spin Choreography: Basic Steps in High Resolution NMR by R. Freeman, Spektrum Academic
Publishers, Oxford, 1997. ISBN g30.00 (hardback only).
0 935702 954,
I approach any book by Ray Freeman with a keen sense of anticipation and with this volume
The authors are to be congratulated on making a notable contribution to the advancement of the subject and I strongly recommend the volume as unique in its coverage and as a useful buy to all individuals and departments with a substantial interest in vibrational spectroscopy. D. C. McKean
Chemistry Department University of Edinburgh Edinburgh UK PI1 Sl386-1425(97)00128-5
Review of Laser Enhanced Ionisation Spectroscopy John C. Travis and Gregory C. Turk,
John Wiley and Sons, ISBN 0 471 576840,&60.00. The key to whether or not one is likely to find this a useful volume may be found in the Preface. The editors explain that a more accurate, if cumbersome title would have been Laser Enhanced Collisional Ionisation Spectroscopy. The Laser Enhanced Ionisation (LEI) to be described is familiar to most spectroscopists in the form of optogalvanic spectroscopy. This book is not therefore primarily concerned with REMPI, LIF or any other members of the alphabet soup that go to make up the collection of techniques employing lasers as ionisation sources. Bearing that restriction in mind this book provides a most useful introduction to the topic of LEI, focusing on the fundamentals, rather than applications. The first two chapters, which occupy approximately half of the book, provide detailed model calculations of ion generation and detection respectively. A simplified kinetic scheme is introduced to describe the ionisation process. It is employed to provide a number of key equations that will aid in the choice of experimental conditions. For example, what is the optimum beam size or excitation wavelength; should one or two colour, pulsed or continuous excitation be employed? The chapter concludes with a density matrix treatment of ion generation, which permits the extension to the cases where Stark broadening
reviews
3191
or direct two photon excitation is important. The chapter on signal detection employs an electrostatic model to calculate the charge transport and current generation following ionisation. A number of practical issues are addressed, and the model is incorporated into a (quick basic) program, which is included as an appendix. The analytical performance of LEI is considered in the third chapter, which contains a rather detailed description of experimental apparatus. There is some overlap between this chapter and those which precede it. A useful table on the experimentally determined detection limit for a number of elements is included. The next chapter contains a bibliography of the application of LEI in flames, while Chapter 5 introduces some non-flame (furnace, plasma, etc.) media. The final chapter describes some more elaborate ionisation schemes which make use of simultaneous measurements of ions and fluorescence. The additional information is interesting, but the more complex nature of the experiments raised some doubts about their analytical uses. Overall this is a well-produced and well-written contribution to the series, containing few errors and a consistent style between chapters. It is. especially in the first two chapters, likely to be of great use to anyone with an interest in the application of lasers in analytical chemistry. This volume is then likely to find a useful place in many chemistry and analytical libraries. S. Meech School of Chemical Sciences University of East Anglia Norwich UK PIZ S1386-1425(97)00129-7
Spin Choreography: Basic Steps in High Resolution NMR by R. Freeman, Spektrum Academic
Publishers, Oxford, 1997. ISBN g30.00 (hardback only).
0 935702 954,
I approach any book by Ray Freeman with a keen sense of anticipation and with this volume