Higher Excited States of Polyatomic Molecules, Volume II focuses on a higher level of activity in vacuum ultraviolet spectroscopy. This book explores the Rydberg states in atoms and molecules. Comprised of five chapters, this volume starts with an overview of the two-center unsaturated molecules that usually display sharp Rydberg transitions originating with the pi electrons. This book then discusses the unsaturated double bond that adds another dimension to the spectrum. Other chapters explore the optical spectrum of the amide group, which is the basic chromophoric unit in polypeptides. This text further discusses the all-electron calculations of the electronic structure of the amide group that is performed in Gaussian orbital basis sets. This book considers as well the prominent characteristic of Rydberg excitations in benzene. The final chapter deals with the biological molecules that are polyfunctional in general. Analytical chemists, photochemists, molecular spectroscopists, and researchers will find this book extremely useful.

Higher Excited States of Polyatomic Molecules, Volume III focuses on higher electronic excitations in polyatomic molecules, with emphasis on excitations beyond 50,000 cm-1. This book explores the various transitions on the basis of their orbital characteristics. Organized into 22 chapters, this volume begins with an overview of the relationships between spectra of different molecules and between the results of various types of spectroscopy. This book then discusses the higher excited states involving Rydberg excitation. Other chapters explore the higher excited states in all classes of biological, organic, and inorganic molecules. This text further discusses the progress in the area of higher excitations in polyatomic atoms and the technique of multiphoton ionization (MPI) spectroscopy that yields a remarkable amount of spectroscopic information applicable to the vacuum-ultraviolet region. The final chapter deals with the vacuum-ultraviolet spectroscopy of biological materials. Analytical chemists, photochemists, molecular spectroscopists, and researchers will find this book extremely useful.

Higher Excited States of Polyatomic Molecules, Volume I focuses on the spectra in the vacuum-ultraviolet region between 50,000 and 100,000 cm-1. This book explores the higher excitations in molecules beyond 50,000 cm-1. Organized into three chapters, this volume starts with an overview of the excited-state properties of a molecule and the excited-state ionization potential. This book then proceeds with a discussion of the original classification of the properties as well as the types of excitations observed in the vacuum-ultraviolet. Other chapters discuss photoelectron spectroscopy, which is an independent, self-sustaining branch of molecular spectroscopy. This text examines as well the distinction between valence shell and Rydberg excitations. The final chapter deals with several topics, including the saturated molecules that are classified as having all valence electrons, the alkene absorption spectra, and the spectroscopic data on boron compounds. Analytical chemists, photochemists, molecular spectroscopists, and researchers will find this book extremely useful.

Higher Excited States of Polyatomic Molecules, Volume II focuses on a higher level of activity in vacuum ultraviolet spectroscopy. This book explores the Rydberg states in atoms and molecules. Comprised of five chapters, this volume starts with an overview of the two-center unsaturated molecules that usually display sharp Rydberg transitions originating with the pi electrons. This book then discusses the unsaturated double bond that adds another dimension to the spectrum. Other chapters explore the optical spectrum of the amide group, which is the basic chromophoric unit in polypeptides. This text further discusses the all-electron calculations of the electronic structure of the amide group that is performed in Gaussian orbital basis sets. This book considers as well the prominent characteristic of Rydberg excitations in benzene. The final chapter deals with the biological molecules that are polyfunctional in general. Analytical chemists, photochemists, molecular spectroscopists, and researchers will find this book extremely useful.

Higher Excited States of Polyatomic Molecules, Volume I focuses on the spectra in the vacuum-ultraviolet region between 50,000 and 100,000 cm-1. This book explores the higher excitations in molecules beyond 50,000 cm-1. Organized into three chapters, this volume starts with an overview of the excited-state properties of a molecule and the excited-state ionization potential. This book then proceeds with a discussion of the original classification of the properties as well as the types of excitations observed in the vacuum-ultraviolet. Other chapters discuss photoelectron spectroscopy, which is an independent, self-sustaining branch of molecular spectroscopy. This text examines as well the distinction between valence shell and Rydberg excitations. The final chapter deals with several topics, including the saturated molecules that are classified as having all valence electrons, the alkene absorption spectra, and the spectroscopic data on boron compounds. Analytical chemists, photochemists, molecular spectroscopists, and researchers will find this book extremely useful.

Higher Excited States of Polyatomic Molecules, Volume III focuses on higher electronic excitations in polyatomic molecules, with emphasis on excitations beyond 50,000 cm-1. This book explores the various transitions on the basis of their orbital characteristics. Organized into 22 chapters, this volume begins with an overview of the relationships between spectra of different molecules and between the results of various types of spectroscopy. This book then discusses the higher excited states involving Rydberg excitation. Other chapters explore the higher excited states in all classes of biological, organic, and inorganic molecules. This text further discusses the progress in the area of higher excitations in polyatomic atoms and the technique of multiphoton ionization (MPI) spectroscopy that yields a remarkable amount of spectroscopic information applicable to the vacuum-ultraviolet region. The final chapter deals with the vacuum-ultraviolet spectroscopy of biological materials. Analytical chemists, photochemists, molecular spectroscopists, and researchers will find this book extremely useful.

From the beginnings of modern chemistry, molecular structure has been a lively area of research and speculation. For more than half a century spectroscopy and other methods have been available to characterize the structures and shapes of molecules, particularly those that are rigid. However, most molecules are at least to some degree non-rigid and this non-rigidity plays an important role in such diverse areas as biological activity, energy transfer, and chemical reactivity. In addition, the large-amplitude vibrations present in non-rigid molecules give rise to unusual low-energy vibrational level patterns which have a dramatic effect on the thermodynamic properties of these systems. Only in recent years has a coherent picture of the energetics and dynamics of the conformational changes inherent in non-rigid (and semi-rigid) molecules begun to emerge. Advances have been made in a number of different experimental areas: vibrational (infrared and Raman) spectroscopy, rotational (microwave) spectroscopy, electron diffraction, and, most recently, laser techniques probing both the ground and excited electronic states. Theoretically, the proliferation of powerful computers coupled with scientific insight has allowed both empirical and ab initio methods to increase our understanding of the forces responsible for the structures and energies of non-rigid systems. The development of theory (group theoretical methods and potential energy surfaces) to understand the unique characteristics of the spectra of these floppy molecules has also been necessary to reach our present level of understanding. The thirty chapters in this volume contributed by the key speakers at the Workshop are divided over the various areas. Both vibrational and rotational spectroscopy have been effective at determining the potential energy surfaces for non-rigid molecules, often in a complementary manner. Recent laser fluorescence work has extended these types of studies to electronic excited states. Electronic diffraction methods provide radial distribution functions from which both molecular structures and compositions of conformational mixtures can be found. Ab initio calculations have progressed substantially over the past few years, and, when carried out at a sufficiently high level, can accurately reproduce (or predict ahead of time) experimental findings. Much of the controversy of the ARW related to the question of when an ab initio is reliable. Since the computer programs are readily available, many poor calculations have been carried out. However, excellent results can be obtained from computations when properly done. A similar situation exists for experimental analyses. The complexities of non-rigid molecules are many, but major strides have been taken to understand their structures and conformational processes.