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1.
    
Raman spectroscopy lends itself to the studies of selenites, selenates, tellurites and tellurates as well as related minerals. The mineral schmiederite Pb2Cu2[(OH)4|SeO3|SeO4], is interesting, in that, both selenite and selenate anions occur in the structure. Raman bands of schmiederite at 1095 and 934 cm−1 are assigned to the symmetric and antisymmetric mode of the (SeO4)2− anions. For selenites, the symmetric stretching mode occurs at a higher position than the antisymmetric stretching mode, as is evidenced in the Raman spectrum of schmiederite. The band at 834 cm−1 is assigned to the symmetric (SeO3)2− units. The two bands at 764 and 739 cm−1 are attributed to the antisymmetric (SeO3)2− units. An intense, sharp band at 398 cm−1 is assigned to the ν2 bending mode. The two bands at 1576 and 1604 cm−1 are assigned to the deformation modes of the OH units. The observation of multiple OH bands supports the concept of a much distorted structure. This is based upon the four OH units coordinating the copper in a square planar structure. A single symmetric Raman band is observed at 3428 cm−1 and is assigned to the symmetric stretching mode of the OH units. The observation of multiple infrared OH stretching bands supports the concept of non‐equivalent OH units in the schmiederite structure. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

2.
    
Selenites and tellurites may be subdivided according to formula and structure. There are five groups, based upon the formulae (a) A(XO3), (b) A(XO3·) xH2O, (c) A2(XO3)3·xH2O, (d) A2(X2O5) and (e) A(X3O8). Of the selenites, molybdomenite is an example of type (a); chalcomenite, clinochalcomenite, cobaltomenite and ahlfeldite are minerals of type (b); mandarinoite Fe2Se3O9·6H2O is an example of type (c). Raman spectroscopy has been used to characterise the mineral mandarinoite. The intense, sharp band at 814 cm−1 is assigned to the symmetric stretching (Se3O9)6− units. Three Raman bands observed at 695, 723 and 744 cm−1 are attributed to the ν3 (Se3O9)6− anti‐symmetric stretching modes. Raman bands at 355, 398 and 474 cm−1 are assigned to the ν4 and ν2 bending modes. Raman bands are observed at 2796, 2926, 3046, 3189 and 3507 cm−1 and are assigned to OH stretching vibrations. The observation of multiple OH stretching vibrations suggests the non‐equivalence of water in the mandarinoite structure. The use of the Libowitzky empirical function provides hydrogen bond distances of 2.633(9) Å (2926 cm−1), 2.660(0) Å (3046 cm−1), 2.700(0) Å (3189 cm−1) and 2.905(3) Å (3507 cm−1). The sharp, intense band at 3507 cm−1 may be due to hydroxyl units. It is probable that some of the selenite units have been replaced by hydroxyl units. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

3.
    
Raman spectroscopy has been used to study the dimorphous selenite minerals chalcomenite, cobaltomenite and clinochalcomenite. Selenite minerals are characterised by the position of the symmetric stretching mode that is observed at higher wavenumbers than the anti‐symmetric stretching mode. The selenite ion has C3v symmetry and four modes, 2A1 and 2E. These modes are observed at 813, 472 cm−1 (A1) and 685, 710, 727 and 367 and 396 cm−1 (E). Bands assigned to the water stretching vibrations are observed for chalcomenite at 2953, 3184 and 3506 cm−1 and for clinochalcomenite at 2909, 3193 and 3507 cm−1. A comparison of the Raman spectra of chalcomenite, clinochalcomenite and cobaltomenite is made. The position of these bands enabled hydrogen bond distances in the selenite structure to be estimated. Hydrogen bond distances for chalcomenite and clinochalmenite were determined to be similar. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

4.
    
Raman spectroscopy has been used to study the selenite mineral ahlfeldite. A comparison is made with the Raman spectra of chalcomenite, cobaltomenite and clinochalcomenite. Selenite minerals are characterised by the position of the symmetric stretching mode which is observed at higher wavenumbers than the anti‐symmetric stretching mode. The selenite ion has C3v symmetry and four modes, 2A1 and 2E. These modes are observed at 813, 472 cm−1 (A1) and 685, 710, 727 and 367 and 396 cm−1 (E). Bands assigned to the water stretching vibrations are observed for ahlfeldite at 3385 cm−1, for chalcomenite at 2953, 3184 and 3506 cm−1 and for clinochalcomenite at 2909, 3193 and 3507 cm−1. A comparison of the Raman spectra of chalcomenite, clinochalcomenite and cobaltomenite is made. The position of these bands enabled hydrogen bond distances in the selenite structure to be estimated. Hydrogen bond distances for ahlfeldite, chalcomenite and clinochalcomenite were determined to be similar. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

5.
    
Raman spectroscopy has been used to study synthetic analogs of the minerals chalcomenite, cobaltomenite, and ahlfeldite occurring in nature. The results obtained are compared with the spectra of these minerals. In general, the majority of vibrational bands of synthetic species are in good agreement with natural chalcomenite, cobaltomenite, and ahlfeldite. The noticeable discrepancies are found for the bands assigned to the deformation mode of selenite groups. A better signal-to-noise ratio realized with synthetic species aids in comprehensive analysis of the spectra, especially in the region of water bands.  相似文献   

6.
    
As one of the milestones in early-era nonlinear Raman studies, Akhmanov et al. [Sov. Phys. JETP 47 , 667 (1978)] and Koroteev et al. [Phys. Rev. Lett. 43 , 398 (1979)] have demonstrated that polarization coherent anti-Stokes Raman scattering (CARS) spectroscopy can resolve overlapping spectral lines that cannot be resolved by means of spontaneous Raman scattering spectroscopy and argued that the resolution of this method is unlimited. Here, we show that information theory offers useful insights into this remarkable result. We demonstrate that spectral super-resolution attainable in polarization CARS can be understood in terms of the Fisher information and the pertinent Cramér–Rao lower bound. We show that, with a suitable polarization arrangement, coherent Raman scattering can be tailored to yield super-resolving spectral modes that provide a nonvanishing Fisher information even for deeply sub-Rayleigh spectral features, preventing the variance of spectral measurements from diverging no matter how fine these spectral features are. When the nonresonant coherent background scattering can be efficiently suppressed, the Fisher information of such super-resolving modes reaches its upper bound as dictated by its quantum version—the quantum Fisher information.  相似文献   

7.
    
Time‐resolved Raman spectroscopy, spatially offset Raman spectroscopy and time‐resolved spatially offset Raman spectroscopy (TR‐SORS) have proven their capability for the non‐invasive profiling of deep layers of a sample. Recent studies have indicated that TR‐SORS exhibits an enhanced selectivity toward the deep layers of a sample. However, the enhanced depth profiling efficiency of TR‐SORS, in comparison with time‐resolved Raman spectroscopy and spatially offset Raman spectroscopy, is yet to be assessed and explained in accordance to the synergistic effects of spatial and temporal resolutions. This study provides a critical investigation of the depth profiling efficiency of the three deep Raman techniques. The study compares the efficiency of the various deep Raman spectroscopy techniques for the stand‐off detection of explosive precursors hidden in highly fluorescing packaging. The study explains for the first time the synergistic effects of spatial and temporal resolutions in the deep Raman techniques and their impact on the acquired spectral data. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

8.
梁瑞生  张坤明 《光学学报》1993,13(5):99-404
介绍喇曼感生克尔效应光谱(RIKES)的琼斯(Jones)矩阵分析方法.探测光束的传输强度不仅由所经过的每一个光学器件的琼斯矩阵所决定,而且还受到强的泵波在非线性介质样品中感生依赖于强度的二向色性和双折射(克尔效应)对琼斯矩阵的影响.同时计及样品和光学器件由强泵波作用下感生应力和其他外部产生的线双折射对喇曼感生克尔效应光谱观察的不利影响,导出测量系统的功率传输函数的完整表达式和喇曼感生克尔效应光谱的实现观察条件,最后简述以甲笨(C_7H_8)液体为试样的喇曼感生克尔效应光谱实验结果分析.  相似文献   

9.
    
Raman spectroscopic techniques are a group of chemical fingerprint detection methods based on molecular vibrational spectroscopy. They are compatible with aqueous solutions and are time saving, nondestructive, and highly informative. With complementary and alternative medicine (CAM) becoming increasingly popular, more people are consuming natural herbal medicines. Thus, chemical fingerprints of herbal medicines are investigated to determine the content of these products. In this study, I review the different types of Raman spectroscopic techniques used in fingerprinting herbal medicines, including dispersive Raman spectroscopy, resonance Raman spectroscopy, Fourier transform (FT)–Raman spectroscopy, surface-enhanced Raman scattering (SERS) spectroscopy, and confocal/microscopic Raman spectroscopy. Lab-grade Raman spectroscopy instruments help detect the chemical components of herbal medicines effectively and accurately without the need for complicated separation and extraction procedures. In addition, portable Raman spectroscopy instruments could be used to monitor the health and safety compliance of herbal products in the consumer market.  相似文献   

10.
    
The aim of this paper is to provide an overview of advances in the field of Raman spectroscopy as reflected in articles published each year in the Journal of Raman Spectroscopy as well as in trends across related journals publishing in this research area. The context for this review is derived from statistical data on article counts obtained from Thomson Reuters ISI Web of Knowledge by year and by subfield of Raman spectroscopy. Additional information is gleaned from presentations featuring Raman spectroscopy presented at the International Conference on Advanced Vibrational Spectroscopy in Kobe Japan in August 2013 and at SCIX 2013 sponsored by the Federation of Analytical Chemistry and Spectroscopy Societies in Milwaukee, Wisconsin, USA, October 2013. Papers published in the Journal of Raman Spectroscopy in 2012 are highlighted in this review and reflect topics and advances at the frontier of Raman spectroscopy, a field that is expanding rapidly as a sensitive photonic probe of matter at the molecular level in an ever widening sphere of novel applications. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

11.
    
The techniques of inverse Raman spectroscopy, Raman‐induced polarization spectroscopy (RIPS), and optical heterodyne RIPS (OHD‐RIPS) are compared by probing the Q‐branch of the nitrogen molecule. The signal is measured employing either a photomultiplier tube (low background level–RIPS) or a photodetector (high background level–IRS and OHD‐RIPS). The measurements are performed using atmospheric mixtures of N2 Ar with concentrations varying from 0 to 79% N2. This strategy permits estimation of detection limits using the different techniques. Pump and probe energy levels are varied independently to study signal dependence on laser irradiance. A theoretical treatment is presented on the basis of the Raman susceptibility equations, which permits the calculation of spectra for all three techniques. Calculated Q‐branch spectra are compared with the measured spectra for the interactions of a linearly polarized probe beam with a linearly or circularly polarized pump beam. The polarizer angle in the detection path for OHD‐RIPS has a dramatic effect on the shape of the spectrum. The calculated and experimental OHD‐RIPS spectra are in good agreement over the entire range of investigated polarizer angles. Detection limits using these techniques are analyzed to suggest their applicability for measuring other species of importance in combustion and plasma systems. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

12.
    
Following the first two reviews on recent advances in linear and non‐linear Raman spectroscopy, the present review summarises papers mainly published in the Journal of Raman Spectroscopy during 2008. This again serves to give a brief overview of recent advances in this research field and to provide readers of this journal a quick introduction to the various sub‐fields of Raman spectroscopy. It also reflects the current research interests and trends in the Raman community. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

13.
The natural abundance carbon-13 nuclear magnetic resonance spectra of diphenic acid and some 6-substituted dibenz [c,e] azepine, 5, 7-dione - which can be considered also as N-substituted diphenimide - were recorded using Fourier transform technique. The chemical shifts of various carbon resonance have been assigned on the basis of chemical shift theory, the signal multiplicity observed in the single frequency off-resonance decoupled (SFORD) spectra and comparison with the chemical shifts of the model compounds.  相似文献   

14.
中国拉曼光谱研究十年（1981—1991）   总被引：2，自引：2，他引：2  
本文介绍了1981～1991年的十年间我国在有机化学、无机化学、生物化学及简正振动分析各领域里拉曼和表面增强拉曼光谱研究的概况。  相似文献   

15.
    
The purpose of the review is to provide a concise overview of recent advances in the broadly defined field of Raman spectroscopy as reflected in part by the many articles published each year in JRS as well as in trends across all related journals publishing in this research area. Context for this review is derived from statistical data on article counts obtained from Thomson Reuters ISI Web of Knowledge by year and by subfield of Raman spectroscopy. Additional information is gleaned from presentations featuring Raman spectroscopy presented at the meetings of the Federation of Analytical Chemistry and Spectroscopy Societies 2011 and the Sixth International Conference on Advanced Vibrational Spectroscopy 2011. Papers published in JRS in 2010, as reviewed here, reflect trends at the cutting edge of Raman spectroscopy, which is expanding rapidly as a sensitive photonic probe of matter at the molecular level with an ever‐widening sphere of novel applications. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

16.
    
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17.
    
Following the first review on recent advances in linear and nonlinear Raman spectroscopy, the present review summarizes papers mainly published in the Journal of Raman Spectroscopy during 2007. This serves to give a fast overview of recent advances in this research field as well as to provide readers of this journal a quick introduction to the various subfields of Raman spectroscopy. It also reflects the current research interests of the Raman community. Similar reviews of highly active areas of Raman spectroscopy will appear in future issues of this journal. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

18.
    
The purpose of this review is to provide a concise overview of recent advances in the broadly defined field of Raman spectroscopy as reflected in part by the many articles published each year in Journal of Raman Spectroscopy as well as in trends across all related journals publishing in this research area. Context for this review is derived from statistical data on article counts obtained from Thomson Reuters ISI Web of Knowledge by year and by subfield of Raman spectroscopy. Additional information is gleaned from presentations featuring Raman spectroscopy presented at the XXIII International Conference on Raman Spectroscopy in Bangalore, India, in August 2012 and at Scientific Exchange 2012 sponsored by the Federation of Analytical Chemistry and Spectroscopy Societies in Kansas City, Missouri, USA, October 2012. Papers published in the Journal of Raman Spectroscopy in 2011 are highlighted in this review and reflect trends at the cutting edge of Raman spectroscopy, a field that is expanding rapidly as a sensitive photonic probe of matter at the molecular level with an ever widening sphere of novel applications. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

19.
    
This article is an overview of advances in Raman spectroscopy published in 2019 in the Journal of Raman Spectroscopy (JRS) and, in addition, trends over the past decade across journals that have published papers important to the field of Raman spectroscopy. The trends are based on statistical data of article counts obtained from Clarivate Analytic's Web of Science Core Collection by year and by subfield of Raman spectroscopy. Normally in this review, coverage would be provided for presentations involving Raman Spectroscopy at the following four international conferences previously scheduled for this year: the International Conference on Raman Spectroscopy (ICORS 2020) in Rome, Italy; SCIX 2020 organized by the Federation of Analytical Chemistry and Spectroscopy Societies (FACSS) in Reno, Nevada, USA, in October; the European Conference on Nonlinear Optical Spectroscopy (ECONOS 2020) in Karlsrue, Germany, in April; and the International Conference on the GeoRaman Spectroscopy (GeoRaman 2020) in Bilbao, Spain, in November (originally scheduled for Weihai, China, in June). Of these, the ICORS 2020 has been rescheduled for 2021 at the same location; ECONOS 2020 has been canceled, but instead, a special issue section is being organized by invitation to commemorate the passing of JRS Board member Marcus Motzkus; SCIX 2020 has been changed to a virtual online conference; GeoRaman 2020 has been canceled, but online submission of abstracts will be made available with selected invitations to submit papers for a special issue of JRS. Finally, papers published in JRS in 2019 are highlighted and arranged by topics at the frontier of Raman spectroscopy. Based on these data, presentations, and publications, it is clear that Raman spectroscopy continues as an expanding field of research across a wide range of novel disciplines and applications that provide sensitive photonic information at the molecular level.  相似文献   

20.
    
This annual review is published to provide an overview of advances in the field of Raman spectroscopy as reflected in papers published each year in the Journal of Raman Spectroscopy (JRS) as well as in trends across related journals that have published papers in the broad field of Raman spectroscopy. The content is obtained from statistical data on article counts obtained from Thomson Reuters ISI Web of Science Core Collection by year and by subfield of Raman spectroscopy. Additional information is gleaned from presentations at the VIII International Conference on Advanced Vibrational Spectroscopy (ICAVS‐8) in Vienna, Austria in July 2015 and those featuring Raman scattering at SCIX 2015 organized by the Federation of Analytical Chemistry and Spectroscopy Societies (FACSS) in Providence, Rhode Island, USA, in September/October 2015. Coverage is also provided for topics from the conference ECONOS 2015 held in April in Leuven, Belgium. Finally, papers published in JRS in 2014 are highlighted and arranged by topics at the frontier of Raman spectroscopy. Taken from these various viewpoints, it is clear that Raman spectroscopy continues to be a rapidly expanding field that provides sensitive photonic information of matter at the molecular level in an ever‐widening arena of novel applications. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

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