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Surface-enhanced infrared absorption spectroscopy (SEIRAS) is a valuable surface-sensitive tool for the investigation of adsorption processes at electrode–electrolyte interfaces. This article gives a brief overview of the current understanding of the enhancement phenomena and describes experimental aspects of electrochemical SEIRAS in detail. The article does not contain detailed theoretical treatments, and only basic knowledge of infrared spectroscopy and electrochemistry is required for understanding the discussion presented.

The combination of near-field microscopy along with nonlinear optical spectroscopic techniques is presented here. The scanning near-field imaging technique can be integrated with nonlinear spectroscopic techniques to improve spatial and axial resolution of the images. Additionally, ultrafast dynamics can be probed down to nano-scale dimension. The review shows some examples for this combination, which resulted in an exciton map and vibrational contrast images with sub-wavelength resolution. Results of two-color femtosecond time-resolved pump-probe experiments using scanning near-field optical microscopy (SNOM) on thin films of the organic semiconductor 3,4,9,10 Perylenetetracarboxylic dianhydride (PTCDA) are presented. While nonlinear Raman techniques have been used to obtain highly resolved images in combination with near-field microscopy, the use of femtosecond laser pulses in electronic resonance still constitutes a big challenge. Here, we present our first results on coherent anti-Stokes Raman scattering (fs-CARS) with femtosecond laser pulses detected in the near-field using SNOM. We demonstrate that highly spatially resolved images can be obtained from poly(3-hexylthiophene) (P3HT) nano-structures where the fs-CARS process was in resonance with the P3HT absorption and with characteristic P3HT vibrational modes without destruction of the samples. Sub-diffraction limited lateral resolution is achieved. Especially the height resolution clearly surpasses that obtained with standard microCARS. These results will be the basis for future investigations of mode-selective dynamics in the near-field.

Attenuated total reflection spectroscopy with tapered fibers is combined to coherent multi-heterodyne spectroscopy in the near-infrared region. Evanescent sensing is extended to broadband high-resolution spectroscopy in the gas phase at high signal-to-noise ratio.

Laser-induced breakdown spectroscopy only provides limited information about chemical products in laser-induced plasmas. In this work, time-resolved resonance fluorescence spectroscopy was studied as a promising tool for the study of chemical reactions in laser-induced plasmas.

Nowadays the development of analytical spectroscopy with high performance, sensitivity and spectral resolution is attended. In the paper the method of two-frequency THz spectroscopy as well as the laboratory model of the spectrometer with using two independent radiation sources and a single detector of THz radiation are presented. The preliminary measurements have testified this new direction of analytical spectroscopy to open widespread trends of its using for various basic and applied problems of physics, chemistry, astronomy, medicine and biology. First of all, there are laboratory modeling the processes of atmospheric and space chemistry, studying of their dynamics as well as transformations and changes of mixture composition. Besides, the method presented can be applied for investigations of fast processes, detecting the intermediate and short time living products of chemical reactions.

Different techniques are used for the sensitive detection of overtone transitions of small molecules, such as H 2 S, C 2 H 2 , OCS, O 3 in the visible and near infrared region. The techniques include: phase-modulated or wavelength-modulation absorption spectroscopy with a widely tunable single mode diode laser, opto-acoustic spectroscopy in resonance cells with a color center laser or a Ti:Sapphire laser, and sub-Doppler opto-thermal spectroscopy in cold collimated molecular beams, using a low temperature bolometer as detector. The three techniques are compared with regard to sensitivity and spectral resolution. The mass selective sensitive detection of small metal clusters Li 3 and Na 3 and their high resolution sub-Doppler spectroscopy, using resonant two-photon ionization with cw lasers, is briefly discussed.

Optical-optical double-resonance spectroscopy with a CW pump laser and dual-comb technique were demonstrated. We obtained the fully resolved hyperfine spectra of rubidium, and the absolute frequencies of the spectra were determined precisely.

An epitome of optical methods used in atomic spectroscopy of radioactive atoms is presented. The overview addresses a number of results in atomic structure and hyperfine structure, and the implications in the study of electric and magnetic properties of nuclei. An apercu is given of the concomitant development of the experimental methods, from simple optical techniques to laser spectroscopy, and from use of “off-line” experiments to ones using ISOLDE-type facilities.

For many years molecular beams were mainly employed for scattering experiments. The combination of new spectroscopic methods with molecular beam techniques has brought about a wealth of new information on the structure of atoms and molecules, on details of collision processes, and on fundamentals of quantum optics and the interaction of light with matter.

In the following review different applications of core-level spectroscopy to atomic and molecular adsorbates will be shown. Core-holes are created through core-level ionization and X-ray absorption processes and the core-hole decays by radiant and non-radiant processes. This forms the basis for X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, Auger electron spectroscopy and X-ray emission spectroscopy. We will demonstrate how we can use the different methods to obtain information about the chemical state, local geometric structure, nature of chemical bonding and dynamics in electron transfer processes. The adsorption of N 2 and CO on Ni(100) will be used as prototype systems for chemisorption while N 2 on graphite and Ar on Pt for physisorption.

The methods for the determination of various types of oxygen surface functions on carbon materials are briefly described, and their relative advantages and problems that may arise are discussed. Acidimetric titration techniques, IR spectroscopy, XPS, thermal desorption spectroscopy, and electrokinetic measurements are described.

The chemical structures of various ion-beam irradiated isotactic-polypropylene samples were studied. Results of micro-Fourier transform infrared spectroscopy and ultraviolet–visible spectroscopy suggest not only the linear energy transfer, but also the fluence is effective in local transformation of the isotactic-polypropylene.

Instrumentation and recent applications of inner-shell electron energy loss spectroscopy of gas phase molecules are reviewed. An overview of recent work in an historical perspective is provided. Comparison is made to the complementary technique of X-ray absorption spectroscopy. Highlights are described of recent applications in: polymer analogue studies, in situ studies of transient species, non-dipole spectroscopy, and systematic measurements of generalized oscillator strengths.

Collinear laser-beam/ion-beam spectroscopy provides a collision-free environment in which to study atomic and molecular ions. Ion-beam spectroscopy has particular advantages over other methods: spectra are relatively simple due to mass selection; kinematics allow sub-Doppler resolution of the whole velocity distribution; and the Doppler effect can be used to tune ions into resonance with fixed frequency light sources. We consider methods by which spectra have been obtained and review important results of ion-beam spectroscopy in fields from nuclear physics to astrophysical chemistry.

The chapter is devoted to a presentation of the main analytical applications of laser spectroscopy in nuclear research and industry. After presenting the analytical needs and the specificity of nuclear analytical applications, the general interest of laser spectroscopy, resulting from the unique performance of laser sources, is discussed. A short review of research performed in the past to develop analytical applications of laser spectroscopy is presented. Finally, three promising techniques, laser-induced breakdown spectroscopy, cavity ring down spectroscopy, and time-resolved laser-induced fluorescence are presented, and some application examples are mentioned.

We describe a novel nonlinear spectroscopy that combines the high signal-to-noise of heterodyne-detected transient-grating spectroscopy with Stark spectroscopy, enabling sensitive detection of charge transfer kinetics. We demonstrate the method on the carotenoid fucoxanthin.

Aspects of laser spectroscopy applied to the biomedical fields are reviewed with examples illustrating the techniques taken mostly from the author's research experience. Basic principles of quantum-mechanical background are described, and powerful implementations in the biophotonics field are discussed.

From the Contents: Cavity-Enhanced Spectroscopy and Sensing.- Introduction to Cavity-Enhanced Absorption Spectroscopy.- Detection and Characterization of Reactive Chemical Intermediates Using Cavity Ringdown Spectroscopy.- Quantum Cascade Laser Based Chemical Sensing Using Optically Resonant Cavities.- Saturated-Absorption Cavity Ringdown (SCAR) for High-Sensitivity and High-Resolution Molecular Spectroscopy in the Mid-IR.- Cavity-Enhanced Absorption Spectroscopy with Optical Feedback.- NICE-OHMS - Frequency Modulation Cavity-Enhanced Spectroscopy - Principles and Performance.- Applications of NICE-OHMS to Molecular Spectroscopy.- Cavity-Enhanced Direct Frequency Comb Spectroscopy.- Whispering Gallery Mode Biomolecular Sensors.- Cavity-Enhanced Spectroscopy on Silica Microsphere Resonators.- Cavity-Ringdown Spectroscopy for the Analysis of Small Liquid Volumes.- Fiber Loop Ringdown Sensors and Sensing.- Fiber-Optic Resonators for Strain-Acoustic Sensing and Chemical Spectroscopy.- Broadband Cavity-Enhanced Absorption Spectroscopy with Incoherent Light.

This chapter critically examines the technical and scientific aspects of vibrational spectroscopy using Raman and nuclear resonance spectroscopy excited with synchrotron radiation (both synchrotron Mossbauer spectroscopy and nuclear resonant inelastic x-ray scattering). These techniques each carry unique, complementary capabilities that permit the study of vibrational, electronic, elastic, and/or thermodynamic properties of planetary materials under a wide range of thermodynamic conditions.

In this chapter, the physical basis and practical implementation of photo-acoustic spectroscopy are described. Fundamental sensitivity limitations imposed by thermodynamic principles are analyzed and compared to limitations of the optical attenuation spectroscopy. Practical designs of photo-acoustic detectors for absorption spectroscopy of gases are described. The impact of intermolecular energy transfer processes on photo-acoustic signal is considered.

High modulus polyacrylonitrile-derived fibres were characterized by X-ray photoelectron spectroscopy, X-ray excited Auger electron spectroscopy and time-of-flight secondary ion mass spectroscopy after d.c. corona discharge treatments under a nitrogen atmosphere at ambient pressure and temperature. The results allow identification of the main functional groups produced by the treatment on the fibre surface and verification of a substantial equivalence of negative- and positive-corona discharge treatments.

A combination of fluorescence spectroscopy and diode laser absorption spectroscopy is used to investigate ageing processes in fruits, where the changes of chlorophyll content and molecular oxygen concentration are mainly studied.

This chapter presents an overview of different complementary techniques used in ultra-fast time-resolved optical spectroscopy experiments in the picosecond and sub-picosecond time range, with particular emphasis on their application to the investigation of the optical and electronic properties of semiconductors.

The magnetic moment and quadrupole moment of the radioactive isotope [sup 143]Pr have been measured by collinear laser-ion-beam spectroscopy. The magnetic moment is found to be [mu](143)=+2.701(4)[mu][sub [ital N]]; the quadrupole moment, [ital Q](143)=+0.77(16)[ital eb]. The experimental values are discussed by comparing them with the theoretical values of pairing-plus-quadrupole, intermediate-coupling, and interacting-boson-fermion models.

Resonance ionization spectroscopy and its combination with mass spectrometry offer very high sensitivity and selectivity. The application of several variants of resonance ionization mass spectroscopy to the study of nuclear ground state properties and trace analysis of radioactive isotopes in the environment is discussed as well as the inverse process, i.e. the laser induced recombination, of bare heavy ions stored at relativistic energies in storage rings.

Methods for the generation and detection of short-lived intermediates are discussed. These include flow systems (where a steady-state concentration of the intermediate is monitored), flash photolysis (where the intermediate is studied in real time using a very fast detection method), and matrix isolation (where the intermediate is preserved by trapping in a solid, inert host at low temperature and where conventional spectroscopic methods are used for detection). Many of the classical experiments utilizing these methods are described, but the relevance to modern chemical studies is also emphasized. The spectroscopic methods used to detect short-lived intermediates are considered. These include nuclear magnetic resonance (NMR), electron spin resonance (ESR), microwave, infrared (IR), Raman, and ultraviolet-visible absorption and emission spectroscopies. It is shown that IR remains the method of choice for matrix-isolation experiments whereas flash photolysis work tends to rely mainly upon electronic spectroscopic techniques. The use of IR spectroscopy, using tunable lasers, for flash photolysis work (at least for slightly longer-lived intermediates) is discussed. Finally two case studies are considered in detail. These are the photolysis of metal carbonyls and the formation of unusual main group compounds at high temperatures. These studies exemplify the procedures that have been used to investigate short-lived intermediates in inorganic chemistry. Keywords: matrix isolation; flash photolysis; flow systems; nuclear magnetic resonance spectroscopy; electron spin resonance spectroscopy; microwave spectroscopy; infrared spectroscopy Raman spectroscopy; ultraviolet-visible spectroscopy; laser-induced fluorescence; extended x-ray absorption fine structure (EXAFS); metal carbonyls; main group compounds; metal halides; metal oxysalts; rare gas chemistry

This article discusses several experimental techniques with Doppler-free spectral resolution such as linear spectroscopy in collimated molecular beams and nonlinear spectroscopy in gas or vapor cells, using saturation spectroscopy, polarization spectroscopy, or multiphoton absorption. Optical cooling of atoms and molecules down to extremely low temperatures brings the Doppler width below the natural linewidth. Special double-resonance schemes enable stabilization of atomic collision pairs and sub-Doppler spectroscopy of molecules in very high-vibrational levels. Finally, some techniques with a resolution below the natural linewidth are discussed. Keywords: laser spectroscopy; molecular beams; saturation spectroscopy; polarization spectroscopy; multiphoton spectroscopy; Doppler width

The spectroscopic study of molecular cations in the gas phase poses a range of challenges which are generally associated with their high chemical reactivity, the difficulties in producing sufficiently high number densities of the desired ion species in a spectrometer, and the limits on the particle densities imposed by the space-charge effect. The present article provides an overview of different experimental techniques that have been developed over the past years to overcome these problems. The topics discussed include highly sensitive laser-based spectroscopic methods (cavity ring-down spectroscopy, frequency-, velocity- and concentration-modulation schemes, and various types of action spectroscopy), the production of internally cold samples of ions and the use of mass-spectrometric methods to select the species of interest out of a mixed sample. Owing to these developments, the range of molecular cations amenable to a spectroscopic characterization has been extended considerably over the past years and now includes various types of cluster ions, protonated biomolecules, ionic carbon chains, and the ions of polycyclic aromatic hydrocarbons. Keywords: high-resolution spectroscopy; cation spectroscopy; cavity ring-down spectroscopy; modulation spectroscopy; action spectroscopy

X-ray absorption spectroscopy (XAS) involves the excitation of core electrons to bound states localized on the photoabsorber and the eventual excitation of the photoelectron to the continuum. The resulting spectra are typically divided into two regions: (1) the edge region which provides electronic structure information and (2) the extended X-ray absorption fine structure (EXAFS) region, which provides information about the distance, number, and type of ligands. Here, a basic introduction to XAS theory, the information that can be obtained, and the experimental consideration are presented. The application of XAS to biological systems and the impact this has had on nitrogenase research are briefly highlighted. New experimental advances are described.

Linear potential sweep and impedance measurements are methods frequently used for studying corrosion behaviour, mass transport processes and the protective properties of coatings applied on metal substrates. Surface-sensitive analytical techniques are useful for understanding the composition and structure of ultra-thin film coatings. Among these techniques, atomic force microscopy (AFM), x-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), specular reflectance infrared, Raman and Mossbauer spectroscopies supply excellent results. Ion spectroscopy and glow discharge optical emission spectroscopy provide information about the concentration and the depth of the elements on the surface of a coating. Finally, electron microscopy provides morphologic and topographic information about the surface of solids.

The possibility for preparing Co3MnOx·nH2O and LiCo3MnOx·nH2O nanolayers by successive ionic layer deposition was examined. The resulting layers were studied by X-ray photoelectron spectroscopy, UV-Vis diffuse reflection spectroscopy, Fourier transmission IR spectroscopy, atomic absorption spectroscopy, ellipsometry, and X-ray powder diffraction.