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Students built two laser beam profilers to measure several laser beam parameters in a university third-year instrumental chemistry laboratory using commercially available optical components used in modern optics research laboratories. While learning about practical properties of laser beams, students utilize laboratory grade optics and optomechanics for precise measurements of the laser beam quality factor, ellipticity, and diameter. Students build and troubleshoot beam profilers using two methods: the classic knife-edge technique as well as by employing a CMOS-based camera. Students recognize the sources of error associated with their constructed profiler, including background intensity, integration time, and lens alignment accuracy when measuring the beam parameters.

Nuclear magnetic resonance spectroscopy (NMR) is a widely used, powerful, and perhaps one of the most important instrumental techniques to qualitatively determine the molecular structure of an analyte. Using proton NMR in quantitative applications, also known as qNMR, is, however, uncommon, particularly in quantifying analytes within a mixture. To increase exposure to both qualitative and quantitative aspects of NMR in an undergraduate chemistry laboratory curriculum, we have developed a straightforward qNMR experiment suitable for adaptation into analytical and instrumental chemistry courses. The objective of this experiment is to determine the weight percent composition of a binary mixture containing short-chain fatty acid ethyl esters. We report on the methodologies used to determine the weight percent composition of ethyl acetate (EtAc), ethyl propionate (EtPr), and ethyl butyrate (EtBu) with mixtures ranging from 0% to 100%. The results demonstrate a strong, linear correlation of the weight percent composition of a selected component in a binary mixture found using proton qNMR with the theoretical compositions calculated gravimetrically. The experiment demonstrates the quantitative utility of proton NMR and serves as an educational tool for the undergraduate chemical laboratory.

The ion-neutralization spectroscopy (INS) is discussed in comparison with other spectroscopies of solids. It is shown that INS probes the local density of states of the solid at or just outside the solid surface. It is believed that this accounts for the clear-cut differences between INS results and those of other spectroscopies. Because of its unique specificity to the surface region INS is particularly useful in studying the surface electronic structures of atomically clean surfaces and of surfaces having ordered arrays of known atoms adsorbed upon them. In the latter case INS determines a portion of the molecular orbital spectrum of surface molecules formed from the adsorbed foreign atom and surface atoms of the bulk crystal. Such spectra provide information on local bonding symmetry and structure and electrical charging within the surface molecule which is as yet unavailable by any other method. INS is the first attempt to base a spectroscopy of electronic states on a two-electron process. More recent work on experimental and mathematical problems which such a spectroscopy entails are also briefly mentioned in this paper.

Nuclear magnetic resonance (NMR) spectroscopy is an analytical technique that is used routinely for the identification of organic compounds. Chemists apply H and carbon (C)-NMR spectroscopy to determine the structure of synthetic organic molecules and natural products. Liquid chromatography has been interfaced with NMR spectroscopy (LC-NMR), which allows the separation of mixtures into individual anionic surfactants and their subsequent detection by means of proton NMR spectroscopy. The application of LC-NMR requires specialized equipment such as an NMR probe with a flow cell. NMR may be used to quantify the relative ratios of the individual components in mixtures or to measure the average alkyl chain length or the number of ethylene oxide units present in a surfactant. The assignment of fatty acid salts by means of NMR spectroscopy relies mainly on the resonance frequency of the C nucleus of the carbonyl moiety. The signals of the fatty acid chain will provide information on the average chain length of the fatty acid.

The experimental determination of atomic levels and the first ionization potential of the heaviest elements ( Z ⩾ 100 ) is key to challenge theoretical predictions and to reveal changes in the atomic shell structure. These elements are only artificially produced in complete-fusion evaporation reactions at on-line facilities such as the GSI in Darmstadt at a rate of, at most, a few atoms per second. Hence, highly sensitive spectroscopic methods are required. Laser spectroscopy is one of the most powerful and valuable tools to investigate atomic properties. In combination with a buffer-gas filled stopping cell, the Radiation Detected Resonance Ionization Spectroscopy (RADRIS) technique provides the highest sensitivity for laser spectroscopy on the heaviest elements. The RADRIS setup, as well as the measurement procedure, have been optimized and characterized using the α -emitter 155 Yb in on-line conditions, resulting in an overall efficiency well above 1%. This paves the way for a successful search of excited atomic levels in nobelium and heavier elements.

The paper presents brief information about the establishment and development in Tomsk of high-resolution molecular spectroscopy – the field of science closely related to a study of the optical properties of the atmosphere. The methods and the current state of high-resolution laser spectroscopy and Fourier spectroscopy are described together with new results of mass measurements. The developed theoretical methods for a study of molecular spectra, including methods of their global analysis and information systems of spectral databases, are presented.

In this chapter, the basic principle, instrumentation, and the analytical potential of resonance Raman spectroscopy (RRS) have been highlighted. The basic principles of Raman and RRS are discussed in the light of Albrecht's “A” and “B” terms. Advancement in Raman instrumentation, after the invention of lasers, is discussed with special emphasis on the source and the detector systems. Analytical applications of RR in agriculture, life sciences, art, archaeology, and forensics are conversed. Recent applications of RRS in carbon nanotube research, exploring the effect of solvent polarity, isomerization dynamics of organic molecules and understanding the contributions of different electronic states of aromatic closed ring compounds to Raman scattering are highlighted. Recent studies on the applications of RRS to understand the excited electronic states of metal–ligand complexes and charge transfer mechanism in halide-substituted hybrid perovskite solar cells are also discussed.

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.

Dissolved organic matter (DOM) is the most reactive organic carbon pool in earth. However, the heterogeneity of this organic mixture makes it difficult to investigate its dynamics under different external perturbations. In this review, we present the potential of using the two dimensional correlation spectroscopy analysis (2D correlations) as a tool to study the dynamic of DOM. We demonstrate the application of the 2D correlation analysis on high molecular weight DOM (HMW-DOM) with the salinity as perturbation parameter. We used four different chemical probes: Carbon nuclear magnetic resonance spectroscopy (13C NMR), Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (1H NMR) and Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS).

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.

We present a novel, cavity-enhanced spectroscopic technique based on a phase-matched Raman process to detect trace quantities of gas. The essence of this technique is the careful control of cavity dispersion to satisfy the phase-matching condition of coherent anti-Stokes Raman scattering (CARS) enhanced in a high-finesse optical cavity. A 6000-fold improvement of the CARS signal is observed under optimized conditions, indicating that this is a promising tool to quantify Raman-active molecules with an extremely low detection limit.

High-resolution resonance ionization spectroscopy (RIS) is required for laser spectroscopy and trace analysis of short-lived and long-lived radioactive nuclei. We have proposed high-resolution resonance ionization spectroscopy in a gas jet combined with a narrow band-width injection-locked Ti:Sapphire laser. Resonance ionization of stable 93Nb in a gas jet was demonstrated using a broad bandwidth Ti:Sapphire laser. In addition, a setup for high-resolution RIS in a gas-jet was designed using numerical simulations of the gas-jet conditions based on computational fluid dynamics.

The advancement of spectroscopy methods attained through increases in sensitivity, and often with the coupling of complementary techniques, has enabled real-time structure and function measurements of single cells. The purpose of this review is to illustrate, in light of advances, the strengths and the weaknesses of these methods. Included also is an assessment of the impact of the experimental setup and conditions of each method on cellular function and integrity. A particular emphasis is placed on noninvasive and nondestructive techniques for achieving single cell detection, including nuclear magnetic resonance, in addition to physical, optical, and vibrational methods.

Using a rather large set of different individual metallic optical antennas, we compare directly measured electron energy-loss spectra with measured quantitative optical extinction and scattering cross-section spectra on the identical antennas. All antenna resonances lie near 1.4 µm wavelength. In contrast to other reports, we find identical resonance positions for electrons and photons to within the experimental errors. We discuss possible artifacts which can lead to seemingly different resonance positions in experiments. Our experimental results agree well with complete numerical calculations of both sorts of spectra.

Accurate spectroscopic measurements of magnetic fields in low mass stars remain challenging because of their cool temperatures, strong line blending, and often fast rotation. This is why previous estimates were based either on the analysis of only a few lines or made use of some indirect techniques. This frequently led to noticeable scatter in obtained results. In this talk I will present and discuss new results on the determination of the intensity and geometry of the magnetic fields in M-dwarfs using IR observations obtained with CRIRES@VLT. The instrument provides unprecedented data of high resolution (R = 100 000) which is crucial for resolving individual magnetically broadened molecular and atomic lines. Such an in-depth analysis based on direct magnetic spectral synthesis opens a possibility to deduce both field intensity and geometry avoiding most of the limitation and assumptions made in previous studies.

FT-IR is quite suitable for studying thin films (or molecular adsorbates) on a solid or liquid surface because of the high sensitivity and quantitatively great reproducibility, which perfectly matches the theoretical prediction based on electrodynamics. Here, the thickness of the thin film is much less than the wavelength of IR light, i.e., a few hundreds of nm or less. In this situation, the optical interfaces of film/air and film/substrate significantly influence the IR spectra even when the simple transmission technique is employed. Since a unique research field of spectroscopy is formed about an interface, this field should be named surface spectroscopy. The theoretical aspect of surface spectroscopy is a little complicated, but the conclusions are concisely summarized as the surface selection rules (SSR). In this chapter, let us imagine a thin film deposited on a substrate, and the physical concept is introduced in detail, followed by the practical applications based on SSR.

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.

The partnering of electrochemical and spectroscopic methods into a single experiment can yield unprecedented insights into the behavior of redox active materials and into interfacial processes. The application of coupled electrochemical and spectroscopic techniques, collectively called spectroelectrochemistry, has grown dramatically over the past three decades to the point that almost every spectroscopic technique available has been applied under potential control. Spectroelectrochemistry has found application across diverse fields from materials science, corrosion, and electronics to biochemistry and its progress has tracked the advances in microscopy and other optical methods providing increasingly detailed insights into electrochemical processes in diverse environments. This chapter describes the experimental considerations and application of spectroelectrochemistry as applied specifically to optical spectroscopy. We describe the experimental demands of applying electrochemical control to spectroscopic experiments across the most common optical formats. We examine specific applications of absorbance, emission, and vibrational spectroscopies under electrochemical control across a range of of materials, including inorganic, supramolecular structures, and polymers. Application of both steady-state and time-resolved spectroscopies to spectroelectrochemistry are examined and finally we anticipate the growing application of spectroelectrochemistry to some of the most recent advances in optical methods, particularly super-resolution methods and single molecule methods.

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.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

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.

Guest editors Matthew Baker and Karen Faulds introduce the Fundamental Developments in Clinical Infrared and Raman Spectroscopy issue of Chemical Society Reviews

An upper-division instrumental chemistry laboratory has been developed in which students use atomic force microscopy (AFM) to collect force curves on polydimethylsiloxane (PDMS) elastomers. Force curves are used to quantify the stiffness of elastomers prepared with different base-to-curing agent ratios. Trends in observed spring constants of the elastomer samples are consistent with Young’s elastic moduli measured in previous studies. This experiment has successfully exposed students to modern instrumental applications addressing surface chemistry in the context of examining cross-linked polymers. Ways to adapt the lab exercise to be used with diverse models of AFM are also discussed.

Both atomic force microscopy (AFM) and Raman spectroscopy are techniques used to gather information about the surface properties of a sample. There are many reasons to combine these two technologies, and this article looks both at the complementary information gained from the techniques and how a researcher having access to a combined system can benefit from the additional information available.

Conformation selective: A new technique of ultraviolet-ultraviolet hole burning spectroscopy that can be applied to ions stored in a quadrupole ion trap (QIT) is developed and used to obtain the conformation-selective electronic spectra of dibenzo[18]crown-6 complexes with alkali metal cations (M(+), see picture; F(+) = fragment).