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Recommendations are given concerning the terminology of concepts and methods used in spectroscopy in analytical chemistry, covering nuclear magnetic resonance spectroscopy, atomic spectroscopy, and vibrational spectroscopy. © 2021 IUPAC and De Gruyter. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. For more information, please visit: http://creativecommons.org/licenses/by-nc-nd/4.0/ 2021.

Understanding the changes that occur when dyes are absorbed onto paper is crucial for the design of new inkjet dyes. This problem is particularly difficult for black dyes that have complex chromophores, and as a result, spectroscopic information on electronic and structural changes can be of importance. Surface-enhanced resonance Raman scattering (SERRS) and electronic structure calculations were used to probe in situ changes in the chromophore in black di-azo dyes printed onto paper. The data indicate that the low-energy chromophore is due mainly to the hydrazone group and the high-energy chromophore to both the azo and hydrazone groups. A comparison of SERRS from the dyes adsorbed onto silver particles in suspension and from the dyes on paper demonstrated a broadening of the chromophore into the red for both dyes and evidence of a structural change in one dye.

Raman scattering for a range of metal phthalocyanines using excitation frequencies from 457.9 to 1064 nm have been interpreted in the light of the recent DFT calculation on zinc phthalocyanine. The intention was to determine the features of the spectra that might be used for in situ analysis of specific phthalocyanines. B1 bands were found to be the most intense. The frequency of one band with a large C–N–C ring displacement is particularly sensitive to the metal ion size. The effect is determined not only by the size of the ion but also by the effect it has on ring shape. First and second order overtone bands of zinc and copper phthalocyanines are broadly similar, with some coupling differences at about 2000 cm−1. The region between 1350 and 1550 cm−1 has been little studied previously. It shows a remarkable sensitivity to the metal ion present and provides a specific signature for each phthalocyanine studied. In contrast, a study of α-, β-, γ- and e-copper phthalocyanines using 514.5 nm excitation showed very few differences, suggesting that intra- rather than intermolecular markers are most efficiently determined by Raman scattering. The study enables the interpretation of the Raman spectra of the phthalocyanines in terms of molecular structure and due to the resonant enhancement involved will enable the in situ identification of specific phthalocyanines in matrices.

The characterization of ink jet dyes and inks printed onto paper surfaces is of importance for the development of ink jet ink formulations and for use in forensic science. Raman spectroscopy is an effective and informative probe for this purpose if problems associated with fluorescence are overcome. A comparison is made here between two effective techniques, surface-enhanced resonance Raman scattering (SERRS) and near-infrared Fourier transform Raman scattering (NIR-FTR). SERRS provides a good method for obtaining in situ measurements using a visible laser system. It is fast (1–10 s accumulations) and requires very low laser powers (200 mW), and the spectral accumulation time is significantly longer. Both methods overcome fluorescence effectively in most samples studied; however, each is more effective than the other with selected inks and paper substrates. SERRS involves resonant enhancement of the chromophore of the dye in contact with the silver surface, and consequently it is the dye chromophore which is uniquely identified. With NIR-FTR, signals from the paper and the filler are also observed. Comparable spectral patterns with clear, explicable differences are obtained from each method, indicating in particular that SERRS spectra can be interpreted without recourse to specific surface selection rules. The combination of the two techniques provides some information on the electronic as well as the vibrational properties of the dyes in situ.

Density functional theory (DFT) calculations have been used to predict the IR and Raman spectra for zinc phthalocyanine (ZnPc). There is very good agreement in the frequency data (RMS error of 10 cm−1 for IR and 12 cm−1 for Raman scattering, with half of the bands in both cases predicted to within 6 cm−1). The precision of the data makes it possible to provide reliable frequency assignments and hence to interpret vibrational changes in terms of structural modifications. The sensitivity of the three IR bands between 700 and 800 cm−1 to the phthalocyanine polymorphic form is explained by the assignment of two modes to out-of-plane vibrations and one mode to an in-plane vibration. The out-of-plane vibrations are expected to be more sensitive to the solid-state packing. The most intense band in the Raman scattering, predicted at 1517 cm−1 for ZnPc, has large displacements on the C–N–C bridge bonds and shifts significantly with metal ion size, making it a good marker for changes in the metal ion environment.

In desultory reading of works not specifically concerned with commerce or the minutiae of trade, one often encounters an intriguing use of terms for length, weight or capacity no longer generally current. This is especially so in diaries, journals and volumes of letters; notes written for the day with no conscious purpose of describing the then present to a readership in the distant future. These entries may often be puzzling since there is no attempt, no need as far as the writer is concerned, to explain the terms he is using. The fortuitous encountering of such entries is a stimulus to interest and the following are a few examples.The diary of James Woodforde (1740–1803), rector of Weston Longeville in Norfolk, records his daily affairs in great detail, especially his expenditure and receipts.

As part of a detailed investigation into the application of GC-FTIR in industrial and environmental analysis, representative sets of samples have been analyzed in parallel using commercial high-sensitivity instruments. Two of the instruments utilize low temperature storage of the GC eluate to extend the time available for FTIR analysis, yielding greater sensitivity than that possible by conventional ‘light-pipe’ GC-FTIR. In certain circumstances, instruments using both types of sample storage give rise to spectra exhibiting features characteristic of the interface used. Chromatographic resolution was found not to be significantly degraded by use of either sample storage interface. Particular advantages were found in having parallel flame ionization detection and mass spectrometry; this enabled the location of smaller components and gave greater certainty of identification.

When gas chromatography/matrix isolation infrared spectroscopy (GCV MI-IR) is carried out with a fixed cryodisk rotation speed, chromatographic resolution may be substantially degraded. In this research, an approach allowing dynamic programming of disk rotation speed is shown to result in much improved resolution in reconstructed chromatograms. Use of up to 254 different speeds during a single chromatographic run is possible. Thus, the analyst can match the requirements of any specific separation problem with an appropriate set of cryocollector movement speeds. As a consequence, much improved analytical performance without loss of sensitivity is possible for mixture analysis by GC/MI-IR, as is up to 30% higher apparent chromatographic resolution than is observed with a flame ionization detector. In addition, careful matching of sample spot size and detector area with the appropriate cryodisk speed leads to the detection of as little as 40 picograms of hexachlorobenzene.

The first use of Kerr gated fluorescence rejection Raman spectroscopy for the analysis of street samples of cocaine in a fluorescing matrix is reported.

The chapter illustrates specific applications of vibrational spectroscopy to colour analysis and colour probes. These include the effects of sample preparation variations for infrared spectroscopy on the colour properties and comparisons of differing laser techniques in Raman spectroscopy relative to the measurement required. A wide range of colour from prehistoric pigments to modern electronic dyes is considered. Several chemical groups, common in colour chemistry, are identified and comments made on the interpretation of the bands. Examples of reactions following tautomerism, hydration, and polymorphism are given. The use of Raman techniques, particularly surface enhanced resonance Raman spectroscopy (SERRS), as colour probes is highlighted and examples of the electronic uses of dyes are given. Brief mention is made of on/at line plant measurements and the spectroscopy of dyes in biological applications. Keywords: infrared; Raman; SERRS; colors; dyes; pigments; polymorphism; tautomerism; electronics

An inter-laboratory comparison has been carried out of three types of GC-FTIR interfacing: light-pipe, matrix isolation, and cryotrapping. Representative samples of industrial and environmental origin have been analyzed in parallel. Instruments utilizing sample storage of the GC-eluent are found to yield considerably better sensitivity than the light-pipe system. The chromatographic resolution was hardly degraded. Spectra obtained often show features characteristic to the interface used. Synchronous use of an FID or MS detector was found to allow better location and identification of the separated components.

The assignment of the vibrational spectra of lithium hydroxide monohydrate, LiOH·H2O, has been controversial for more than half-a-century. Here we show that only the combination of all three forms of vibrational spectroscopy: infrared, Raman and inelastic neutron scattering spectroscopies coupled with periodic-density functional theory calculations is able to satisfactorily assign the spectra. All previous work based on empirical criteria is, at least partially, incorrect. The librational modes of water do not follow the expected rock > wag > twist order and the calculations indicate that complete or partial deuterium substitution would not be useful in assigning the modes.

Poly(aryl)amine based charge transfer materials (CTMs) are essential components in a range of present and future technologies, from the Xerox process to display devices based upon light emitting polymers (LEPs). However, there is a lack of detailed understanding regarding the electronic properties of CTMs in their various neutral and oxidized forms. This paper reports the use of an optically transparent thin layer electrochemical (OTTLE) cell in combination with a Raman microprobe system and DFT calculations to provide information on the molecular and electronic structure of the mono- and di-oxidized derivatives of the classic CTM N,N′-diphenyl-N,N′-bis(3-methylphenyl)(1,1′-biphenyl)-4,4′-diamine (TPD) and the closely related species N,N′-diphenyl-N,N′-bis(2,4-dimethylphenyl)(1,1′-biphenyl)-4,4′-diamine (DMTPD). The resonance Raman scattering profile easily discriminates between the monovalent and divalent cations while DFT calculations permit correlation of the observed vibrational frequencies with localized atomic displacements. The cations are best described in terms of a symmetrical (i.e. fully delocalized) structure. The high sensitivity of the method suggests that it should be appropriate for the observation of low concentrations of the various cations generated from TPD type CTMs during device operation.

Surface-enhanced resonance-Raman scattering (SERRS) experiments using a citrate-coated silver colloid have been performed. Transmission electron microscopy showed that the colloid consists of nearly mondisperse hexagonal particles with a maximum dimension of 36 nm. For maximum sensitivity, SERRS requires the controlled aggregation of the colloid. The nature of the aggregate formed is dependent on the method of aggregation. The effect of poly-L-lysine on the aggregation procedure was characterised using transmission and scanning electron microscopy. With SERRS, sensitivities down to 6.87 × 10–18 mol dm–3 were obtained using rhodamine dye. This corresponds to less than 200 molecules in the beam at any one time and suggests a sensitivity equal to or greater than that of fluorescence. A comparison of the use of SERRS with surface-enhanced Raman scattering (SERS) to follow adsorbate reactivity on a surface at less than monolayer coverage was obtained by studying metal complex formation using a preresonant Schiff base (SERRS) and 2-hydroxy-1-naphthaldehyde excited off resonance (SERS). In the former case, complex formation on the surface at well below monolayer coverage was observed and differences between the surface and the bulk complex characterised. In the latter complex formation was again observed but the bands were broad and problems of contamination, photodecomposition and selectivity evident.

The wapentakes of Staincliffe and Ewcross occupy the northern extremity of Yorkshire's West Riding where it abuts upon Westmorland and north Lancashire. The greater part of the region lies upon the Askrigg Massif and consists of a deeply dissected plateau on which extensive moorlands are interrupted by dales of differing fertility (Fig. 1). Apart from a few inliers of Lower Palaeozoic formation in Ewcross, the rocks are Carboniferous Limestones and Yoredales, with Millstone Grit capping only the higher summits. The limestones provide a neutral soil rich in calcium, but modification by glacial drift produces much coarse herbage and extensive peat mosses. In the southern part of Staincliffe there is a small drumlin swarm in the Craven Lowlands, but Millstone Grit predominates and, as a result of strong east-west faulting, is thrown down for the most part to a lower elevation than the limestone country.

According to one scholar ‘Some historical materials are intended to convey information, some to entertain only, and some to deceive. Some are aimed at contemporaries, some are aimed at posterity and some are not aimed at all’. Nowhere is the truth of this statement more evident than in the use of historical material involving weights and measures, and the purpose of what follows is to illustrate with examples howmisleading apparently factual material may be unless it is recognized that there was much less uniformity than some sources would suggest.

In European ethnology we are rightly concerned with the development of agriculture, the techniques by which natural resources have been exploited, and the infinite variety of social structures, customs, and traditions associated with these activities. Yet it is perhaps worthwhile to remind ourselves occasionally that man was a hunter for over a million years and has been a cultivator for but a few thousand. Indeed it was as a hunter/gatherer that he colonized all habitable parts of the earth's surface, maintaining himself everywhere with spear and club, hook and snare.The origins of these tools, then, lie far back in the history of mankind and they occur in every part of the world. Perhaps because of this enormous range, both temporal and spatial, they display a remarkable homogeneity of form and though details of construction may be influenced by the materials available, the true determinants of their basic design are demonstrably still those imposed by the nature of the quarry and the conditions...

In a previous article attention was drawn to the many customary systems of weights and measures used in the past in different parts of the country. Since many of them remained in use until the late nineteenth century, it was suggested that familiarity with the customary measures formerly current in the study area was essential before drawing conclusions from documentary evidence originating in an earlier period. In that context little was said about the fundamental relationship between weight and coinage, and this short note is an attempt to rectify that omission. With a centralized monetary system since before the Conquest the apparent anomalies were not themselves regional, but since different weight and valuation systems were often applied to different commodities, the importance of their correct interpretation may be readily appreciated.

Of the many small stones once thought to possess magical powers the naturally holed pebble used as a simple protective amulet is of particular interest, because of its wide geographical range and marked uniformity of purpose. The dangers from which it supposedly afforded protection are many, ranging in importance from nightmare to plague and including in its scope such hazards as mine accidents, storm at sea and famine. Yet its primary function was to provide immunity from the perils of witchcraft and it is suggested that the many apparently distinct usages do not, in fact, indicate any fundamental difference of belief, but rather bear witness to the variety of common misfortune formerly attributed to the activities of witches.

In an account of markets and fairs there can be no escape from a recital of charter dates, a review of franchise and prescription and at least some mention of Courts of Pie Powder and the Assize of Bread and Ale. But the present paper is not a treatise on market law and is really concerned with these events as gatherings of people; whatever the motives of those who sought franchise of the Crown, the real beneficiaries, in the long term, were ordinary market users. And so, whilst it is first necessary to summarise the legal position, this is intended to be no more than a preliminary to a consideration of the part these ancient institutions played in bringing colour and variety into the lives of the rural population.