摘要:

The phenomenon of lattice relaxation, namely, that the atomic configuration surrounding a localized centre in solids changes with its change of electronic state, leads to various forms of multiphonon transitions. In optical emission or absorption spectra, such multiphonon transitions can cause shift and broadening of the spectral lines or give rise to distinct multiphonon peaks. Certain basic theoretical concepts relating to such multiphonon optical spectra are explained and a special discussion of the proper interpretation of the Franck-Condon principle in this connection is given. Lattice relaxation can also give rise to nonradiative transitions, which are important for carrier recombinations in semiconductors and quenching of luminescence.

ISSN:0010-7514    

DOI:10.1080/00107518108231558

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

This article reviews experimental and theoretical work on the spectrum of ice. Its features in the radiofrequency region arise from the reorientation of water molecules at lattice sites where strong thermal excitations of a molecular vibration produce a defect. The large permittivity and relaxation time in ice are consistent with our knowledge of its structure. The microwave region has been less extensively studied, but enough information is available to determine how the molecular polarizability of a water molecule in ice depends upon temperature and volume. In the infrared region, two features, arising from the translational lattice vibrations and symmetric O-H stretching, have received much attention, and progress is being made towards understanding them theoretically. The visible and ultraviolet regions show no distinctive features, and the absorptivity in this region is small.

ISSN:0010-7514    

DOI:10.1080/00107518108231559

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Over the past two decades, observational studies using aircraft and satellite data to supplement conventional surface and upper air data have revealed much about the structure of tropical cyclones. During this same period, numerical weather prediction models have been developed to study the dynamics and energetics of these intense, destructive storms. This article reviews the structure of mature tropical cyclones and discusses the physical processes that are important in their genesis and maintenance. Some examples of computer simulation models are presented. Finally, the operational prediction of actual tropical storms by statistical and dynamical methods is summarized.

ISSN:0010-7514    

DOI:10.1080/00107518108231560

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0010-7514    

DOI:10.1080/00107518108231561

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0010-7514    

DOI:10.1080/00107518108231562

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Electrical Transport in Solids. By Kwan C. Kao and Wei Hwang. (Pergamon Press, 1981.) [Pp. xx+663.] £50.00; $100.00. Scope: Treatise; Textbook. Level: Specialist; postgraduate.

ISSN:0010-7514    

DOI:10.1080/00107518108231563

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0010-7514    

DOI:10.1080/00107518108231564

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor