Optical Spectroscopy

This laboratory manual originated from eighteen years of teaching the
class Inorganic Preparations, which follows the Descriptive Inorganic
Chemistry course in the Inorganic Chemistry curriculum of Missouri State University (USA). Both courses are designed for chemistry majors. They represent a logical progression and harmonic combination of theoretical background in the discipline at first, with enhancement and retention of gained knowledge during following experimental laboratory work. This course is designed for lab sessions of four hours each.
The book provides an extensive and necessary introduction for students to typical glassware and lab equipment (labware) which are normally used in the synthetic chemistry laboratory. This introduction is followed by a brief description of the main laboratory procedures and operations that are essential for safe and productive laboratory work. These were limited to: filtration, extraction, distillation and reflux, work with vacuum,
anaerobic/moisture free procedures, flash column and preparative thinlayer chromatography, and products recovery from solutions. In this
context it is very important to note that this laboratory manual is neither
intended to promote or advertise any of the equipment brands and their
manufacturers, nor it is intended to show off, or brag about the laboratory capabilities that exist at the authors’ institutions! In fact, the glassware, apparatuses and equipment used in this book fit very well into the average teaching and research facilities typical of numerous institutions of higher education around the world. Moreover, during the description of laboratory glassware, hardware and laboratory methods at the beginning of this manual, special attention is drawn to inexpensive alternative solutions when building equipment for common procedures, as well as to cost-saving lab techniques.

All preparative experiments are designed for the synthesis of grams’
quantities of compounds. This ensures students’ satisfaction with the
whole process of the synthesis, work-up procedures and post-lab handling of substances, many of which will be further studied. This manual is heavily illustrated with 224 figures, 12 schemes and 20 tables, to aid students in carrying out all experiments and to help them learn laboratory techniques. The main purpose of such an illustrative approach is to go in step with a new and younger generation of visual learners, who, in the digital age of the internet and mobile devises, truly value the old sentiment that ‘a picture is better than a thousand words’. Almost all illustrative material was produced by the authors, taking photographs from actual lab equipment and setups, or making drawings using freely available software.

Before the description of many experiments and characterizations of the
obtained compounds, there are brief and condensed sections of theoretical background information. These allow the reader to get familiar with the topic that follows. Thus, the following physical methods and techniques are presented in these short introductory sections: 1) thermal analysis, 2) X-ray diffraction methods, 3)  molecular weight determination - cryoscopic measurements, 4)
cyclic voltammetry measurements in solutions, 5) solutions electrical conductivity measurements, 6) magnetochemistry in solid state and in solution, 7) spectroscopy (vibrational, electronic, 1H and 13C NMR).

The concept of indirect learning has been used by authors for many years. In our academic settings, that means splitting a class of students into two equal groups, both of which conduct the same kind of experimental preparations, but use different compounds and some alternative work-up and samples handling details. There are laboratory exercises with extensions A, B, or C. Being in the same laboratory for four hours, students, in an indirect way, learn what their peers in the other group are working on. All experiments are presented in clear, step-by-step fashion to help students to carry out particular syntheses, conduct important procedures, and accomplish necessary measurements. All sections in the book are supplied with appropriate literature references for the reader interested in further learning.
During the course of these lab experiments, suitable single crystals of several compounds were grown by students, and subsequently characterized using the X-ray analysis. The main results of this work are
presented and discussed in this manual, with all CIFs for five determined
structures deposited into the Cambridge Crystallographic Data Center
(CCDC).

Therefore, a combination of specially selected series’ of experiments,
with alternative lab work, accompanied with paragraphs of short and
concise theoretical background, and detailed examples of calculations,
make this book truly unique in the modern academic environment. This
book also can be a useful reference for other synthetic chemists not limited to the inorganic/coordination chemistry field, who will be interested in the interpretation of vibrational, electronic, and - more importantly – 1D and 2D NMR spectra.

In summary, according to numerous students' feedback and evaluations, it is engaging, very intense, and yet likeable, and is considered to be a useful class. It has been a popular laboratory course, with 120+ chemistry majors who have enjoyed taking it, thus far.

The primary focus of this paper is building a relatively low-cost Photospectrometer in comparison to general high-cost photo spectrometers available along with a generative idea on using tweak and how different components can be used in designing an effective device for chemical applications. This Photospectrometer shall be also using a power source of lower values. Using appropriate dimensions and components the accuracy of measurement can be significantly improved. Basic components include using an LED as a light source, a diffraction grating, cuvettes, a sensor, and a programmable device for output measurement. The building of this Photospectrometer can be performed easily at home and in projects and a key feature includes detachability of components for space optimization and component alteration if necessary. The two designs proposed in this paper give significant results which when applied on different solutions making it feasible to be used at lower level spectroscopy purposes.

The unique reddish blood stains on the archaeological cloth known as the Shroud of Turin caught the attention of several scholars, who proposed different hypotheses to explain the unusual blood color. To date, just few hypotheses have been tested experimentally, and the results are debatable.
In this paper we test the strength of two hypotheses (namely, the presence of carboxyhemoglobin and the long term influence of ultraviolet light on high-bilirubin blood) by the spectral reflectance of the blood stain regions on the Shroud and by color analyses of ultraviolet irradiated high-bilirubin blood stains on linen.
The relevance of these simple methods to the study of stained textiles is discussed.

Publication of the 29th International Colloquium of the Corpus Vitrearum. "Stained glass in the 17th century. Continuity, Invention, Twilight", Antwerp, 2-6 July 2018. Edited by Madeleine MANDERYCK, Isabelle LECOCQ and Yvette VANDEN BEMDEN, Antwerp/Brussels, 2018.

In laser spectroscopy, the interaction of light emitted from various types of laser sources – tunable or nontunable in their output frequency – with the atomic or molecular species of interest is used to probe the sample through a variety of spectral responses. In order to perform laser spectroscopy, suitable laser sources must be selected, which meet the requirements of the chosen spectroscopic method. This means that the laser has to provide radiation in the wavelength range of interest, has the appropriate emission characteristics (lineshape), and has a suitable energy to perform the measurements. Further requirements are pulse length (milliseconds to femtoseconds or continuous wave), repetition rate, and beam profile. Nowadays, laser radiation can be generated with most of the required parameters necessary for the respective spectroscopic application, either directly or by generating new radiation frequencies by frequency mixing of one or several laser beams in a nonlinear medium (gas, liquid, and solid).
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https://doi.org/10.1002/9780470027318.a0715.pub3
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The quality of virgin olive oils is assessed through the determination of several analytical parameters, whose values must be within the ranges established by the different institutions involved. In addition to official methods, there is a strong need for simple, rapid, and environmentally friendly techniques for the quality control of virgin olive oils and for addressing the challenging task of determining geographical origin and detecting adulterants. Toward this purpose, some of the most interesting applications based on optical spectroscopic techniques, on the measurement of electrical characteristics and on the use of instruments equipped with electronic chemical sensors, including also other promising techniques are herein discussed. These techniques, adequately coupled with an appropriate statistical approach, appear to be promising for assessment of several quality-related parameters. The prediction of sensory attributes and of the oxidative status of virgin olive oils have also been reviewed by adopting these selected techniques, which are also considered to be potentially appropriate solutions for identification of the geographical origin of virgin olive oils and to assess their adulteration with cheaper oils. Overall, the techniques discussed are promising and cutting-edge approaches for the establishment of useful portable instruments for in situ monitoring of the quality of virgin olive oils. Practical applications: The simple, rapid, and environmentally friendly analytical approaches discussed herein represent promising analytical tools for assuring the authenticity and monitoring the quality of virgin olive oils. Such innovative techniques and tools need to be ring-tested and validated. Some innovative reviewed approaches will permit to develop useful portable instruments able to perform in situ appropriate controls also by small laboratories or olive oil mills with limited technical facilities. These equipments will be potentially usable also by trained " non-professional analytical skilled " people. Some other approaches, rapid but more expensive, will be applicable mainly by quality control labs and will increase the number of samples analyzed per day, thus fostering laboratory proficiency and an effective fighting against olive oil fraud.

The study tested a data mining engine (PARACUDA ®) to predict various soil attributes (BC, CEC, BS, pH, C org , Pb, Hg, As, Zn and Cu) using reflectance data acquired for both optical and thermal infrared regions. The engine was designed to utilize large data in parallel and automatic processing to build and process hundreds of diverse models in a unified manner while avoiding bias and deviations caused by the operator(s). The system is able to systematically assess the effect of diverse preprocessing techniques; additionally, it analyses other parameters, such as different spectral resolutions and spectral coverages that affect soil properties. Accordingly, the system was used to extract models across both optical and thermal infrared spectral regions, which holds significant chromophores. In total, 2880 models were evaluated where each model was generated with a different preprocessing scheme of the input spectral data. The models were assessed using statistical parameters such as coefficient of determination (R 2), square error of prediction (SEP), relative percentage difference (RPD) and by physical explanation (spectral assignments). It was found that the smoothing procedure is the most beneficial preprocessing stage, especially when combined with spectral derivation (1st or 2nd derivatives). Automatically and without the need of an operator, the data mining engine enabled the best prediction models to be found from all the combinations tested. Furthermore, the data mining approach used in this study and its processing scheme proved to be efficient tools for getting a better understanding of the geochemical properties of the samples studied (e.g., mineral associations).