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Nuclear magnetic resonance spectroscopy, which has evolved only
within the last 20 years, has become one of the very important
tools in chemistry and physics. The literature on its theory and
application has grown immensely and a comprehensive and adequate
treatment of all branches by one author, or even by several,
becomes increasingly difficult. This series is planned to present
articles written by experts working in various fields of nuclear
magnetic resonance spectroscopy, and will contain review articles
as well as progress reports and original work, its main aim,
however, is to fill a gap, existing in literature, by publishing
articles written by specialists, which take the reader from the
introductory stage to the latest development in the field. The
editors are grateful to the authors for the time and effort spent
in writing the articles, and for their invaluable cooperation. The
Editors Contents P. Diehl and C. L. Khetrapal NMR Studies of
Molecules Oriented in the Nematic Phase of Liquid
Crystais......................................................... 1
R. G. Jones The Use of Symmetry in Nuclear Magnetic
Resonance................. 97 NMR Studies of Molecules Oriented in
the Nematic Phase of Liquid Crystals P. DIEHL and C. L. KHETRAPAL *
Department of Physics, University of Basel, Switzerland Contents 1.
Introduction . . . . . . . . . . . . . . . . . . . .. . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . 3 2. Liquid Crystals
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
. . . . . . . . . . . . . . 2.1. Classification of Liquid Crystal
Phases . . . . . . . . . . . . . . . . . . . . . . . 4 2.2.
Theories of the Liquid Crystalline State . . . . . . . . . . . . .
. . . . . . . . . 5 2.3. Nematic Phases . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.
Experimental . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . 7 1 4. Basic Theory
(for I = I ). . . . . . . . . . . . . * . . . . . . . . . . . . . .
. . . . . . . . . 7 . .
1. Lyotropic Liquid Crystals The class of compounds known as
thermotropic liquid crystals has been widely utilized in basic
research and industry during recent years. The properties of these
materials are such that on heating from the solid to the isotropic
liquid state, phase transitions occur with the formation of one or
more intermediate anisotropic liquids. The unique and sometimes
startling properties of these liquid crystals are the properties of
pure compounds. However, there exists a second class of substances
known as lyotropic liquid crystals which obtain their anisotropic
properties from the mixing of two or more components. One of the
components is amphiphilic, containing a polar head group (generally
ionic or zwitterionic) attached to one or more long-chain
hydrocarbons; the second component is usually water. Lyotropic
liquid crystals occur abundantly in nature, particularly in all
living systems. As a consequence, a bright future seems assured for
studies on such systems. Even now, many of the properties of these
systems are poorly understood. It is the purpose of this review to
consolidate the results obtained from nuclear magnetic resonance
studies of such systems and to provide a coherent picture of the
field. Probably the most familiar example of a lyotropic liquid
crystal is soap in water. A common soap is sodium dodecylsulphate
where an ionic group (sulphate) is attached to a hydrocarbon chain
containing twelve carbons.
Nuclear magnetic resonance spectroscopy, which has evolved only
within the last 20 years, has become one of the very important
tools in chemistry and physics. The literature on its theory and
application has grown immensely and a comprehensive and adequate
treatment ofall branches by one author, or even by several, becomes
increasingly difficult. by experts workinginvarious This seriesis
planned to present articles written fields of nuclear magnetic
resonance spectroscopy, and will contain review articles as well as
progress reports and original work. Its main aim, however, is to
fill a gap, existing in literature, by publishing articles written
by specialists, which take the reader from the introductory stage
to the latest development in the field. The editors are grateful to
the authors for the time and effort spent in writing the articles,
and for their invaluable cooperation. The Editors Computer
Assistance in the Analysis of High-Resolution NMR Spectra P. DIEHL
and H. KELLERHALS Departmentof Physics, University ofBasle,
Switzerland E. LUSTIG Food and Drug Administration, Washington,
D.C., U.S.A.
Nuclear magnetic resonance spectroscopy, which has evolved only
within the last 20 years, has become one of the very important
tools in chemistry and physics. The literature on its theory and
application has grown immensely and a comprehensive and adequate
treatment of all branches by one author, or even by several,
becomes increasingly difficult. This series is planned to present
articles written by experts working in various fields of nuclear
magnetic resonance spectroscopy, and will contain review articles
as well as progress reports and original work. Its main aim,
however, is to fill a gap, existing in literature, by publishing
articles written by specialists, which take the reader from the
introductory stage to the latest development in the field. The
editors are grateful to the authors for the time and effort spent
in writing the articles, and for their invaluable cooperation. The
Editors Contents o. Kanert and M. Mehring Static Quadrupole Effects
in Disordered Cubic Solids 1 F. Noack Nuclear Magnetic Relaxation
Spectroscopy 83 Static Quadrupole Effects in Disordered Cubic
Solids O. KANERT and M. MEHRING Physikalisches Institut der
Universitat MUnster, BRD Contents I. Introduction. . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . 3 II. Fundamentals . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Zero
Field Spectra . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . 4 2. High Field Spectra . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.
Transformation of the Electric Field Gradient Tensor . . . . . . .
. . . 7 III. The Influence of the Quadrupole Perturbation on the
NMR Signal . 8 1. General Theory . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . 8 a) The Free
Induction Decay . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . 8 b) The Wide-Line Signal . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . 11 c) The Spin Echo Signal .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .: . .
Nuclear magnetic resonance spectroscopy, which has evolved only
within the last 20 years, has become one of the very important
tools in chemistry and physics. The literature on its theory and
application has grown immensely and a comprehensive and adequate
treatment of all branches by one author, or even by several,
becomes increasingly difficult. This series is planned to present
articles written by experts working in various fields of nuclear
magnetic resonance spectroscopy, and will contain review articles
as well as progress reports and original work. Its main aim,
however, is to fill a gap, existing in literature, by publishing
articles written by specialists, which take the reader from the
introductory stage to the latest development in the field. The
editors are grateful to the authors for the time and effort spent
in writing the articles, and for their invaluable cooperation. The
Editors Contents c. W. Hilbers and C. MacLean NMR of Molecules
Oriented in Electric Fields.
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