A Acronyms

CCSD-F12 Full explicitly correlated coupled-cluster singles-and-doubles 

MP2 Second order Mpller-Plesset perturbation theory 

ROHF Restricted open-shell Hartree-Fock 

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The acronym "CIAPES" stands for - Controle et Inspection des Appareils a pression lors de I Epreuve et en Service (Control and Inspection of Pressure Vessels during Testing and in Service). 

The function of this chapter is to review these methods with emphasis on the types of phenomenology involved and information obtained. Many of the effects are complicated, and full theoretical descriptions are still lacking. The wide variety of methods and derivative techniques has resulted in a veritable alphabet soup of acronyms. A short list is given in Table VIII-1 (see pp. 313-318) the lUPAC recommendations for the abbreviations are found in Ref. 1. 

The listing of techniques in Table Vlll-1 is not a static one. It is expanded over what it was a few years ago and is continuing to expand. Try, in an imaginative yet serious manner, to suggest techniques not listed in the table. Explain what their values might be and, of course, propose a suitable acronym for each. 

Several instniments have been developed for measuring kinetics at temperatures below that of liquid nitrogen [81]. Liquid helium cooled drift tubes and ion traps have been employed, but this apparatus is of limited use since most gases freeze at temperatures below about 80 K. Molecules can be maintained in the gas phase at low temperatures in a free jet expansion. The CRESU apparatus (acronym for the French translation of reaction kinetics at supersonic conditions) uses a Laval nozzle expansion to obtain temperatures of 8-160 K. The merged ion beam and molecular beam apparatus are described above. These teclmiques have provided important infonnation on reactions pertinent to interstellar-cloud chemistry as well as the temperature dependence of reactions in a regime not otherwise accessible. In particular, infonnation on ion-molecule collision rates as a ftmction of temperature has proven valuable m refining theoretical calculations. 

The 70 years since these first observations have witnessed dramatic developments in Raman spectroscopy, particularly with the advent of lasers. By now, a large variety of Raman spectroscopies have appeared, each with its own acronym. They all share the conunon trait of using high energy ( optical ) light to probe small energy level spacings in matter. 

Many variations of the basic homonuclear COSY experiment have been devised to extend its range. A brief guide to some classes of experiment follows, along with a few of the connnon acronyms. 

A H(detected)- C shift correlation spectrum (conmion acronym HMQC, for heteronuclear multiple quantum coherence, but sometimes also called COSY) is a rapid way to assign peaks from protonated carbons, once the hydrogen peaks are identified. With changes in pulse timings, this can also become the HMBC (l eteronuclear multiple bond coimectivity) experiment, where the correlations are made via the... 

ELDOR is tlie acronym for electron-electron double resonance. In an ELDOR experiment [28] one observes a rednction in the EPR signal intensity of one hyperfme transition that results from the saturation of another EPR transition within the spin system. ELDOR measurements are still relatively rare bnt the experiment is fimily established in the EPR repertoire. 

We make one important note here regarding nomenclature. Early explanations of CIDNP invoked an Overhauser-type mechanism, implying a dynamic process similar to spin relaxation hence the word dynamic m the CIDNP acronym. This is now known to be incorrect, but the acronym has prevailed in its infant fomi. 

From the above descriptions, it becomes apparent that one can include a wide variety of teclmiques under the label diffraction methods . Table Bl.21.1 lists many techniques used for surface stmctural detemiination, and specifies which can be considered diffraction methods due to their use of wave interference (table Bl.21.1 also explains many teclmique acronyms commonly used in surface science). The diffraction methods range from the classic case of XRD and the analogous case of FEED to much more subtle cases like XAFS (listed as both SEXAFS (surface extended XAFS) and NEXAFS (near-edge XAFS) in the table). 

PD (covers a variety of other acronyms, like ARPEFS, ARXPD, ARXPS, ARUPS, NPD, OPD, PED) yes 88 7.9... 

The acronym LASER (Light Amplification via tire Stimulated Emission of Radiation) defines the process of amplification. For all intents and purjDoses tliis metliod was elegantly outlined by Einstein in 1917 [H] wherein he derived a treatment of the dynamic equilibrium of a material in a electromagnetic field absorbing and emitting photons. Key here is tire insight tliat, in addition to absorjDtion and spontaneous emission processes, in an excited system one can stimulate tire emission of a photon by interaction witli tire electromagnetic field. It is tliis stimulated emission process which lays tire conceptual foundation of tire laser. 

J nputcitional quantum chemistry is well endowed with acronyms and abbreviations. A list of some ot the more common ones can be found in Appendix 2.1,... 

Quantum chemists have devised efficient short-hand notation schemes to denote the basis set aseti in an ab initio calculation, although this does mean that a proliferation of abbrevia-liijii.s and acronyms are introduced. However, the codes are usually quite simple to under-sland. We shall concentrate on the notation used by Pople and co-workers in their Gaussian aerie-, of programs (see also the appendix to this chapter). 

Bioinformatics is a relatively new discipline that is concerned with the collection, organisatic and analysis of biological data. It is beyond our scope to provide a comprehensive overvie of this discipline a few textbooks and reviews that serve this purpose are now available (s the suggestions for further reading). However, we will discuss some of the main rnethoc that are particularly useful when trying to predict the three-dimensional structure and fum tion of a protein. To help with this. Appendix 10.1 contains a limited selection of some of tf common abbreviations and acronyms used in bioinformatics and Appendix 10.2 lists sorr of the most widely used databases and other resources. 

The notation for denoting this type of calculation is sometimes more specihc. For example, the acronym MCSCF+1+2 means that the calculation is a MRCI calculation with single and double Cl excitations out of an MCSCF reference space. Likewise, CASSCF+1+2 and GVB+1+2 calculations are possible. 

A second issue is the practice of using the same set of exponents for several sets of functions, such as the 2s and 2p. These are also referred to as general contraction or more often split valence basis sets and are still in widespread use. The acronyms denoting these basis sets sometimes include the letters SP to indicate the use of the same exponents for s andp orbitals. The disadvantage of this is that the basis set may suffer in the accuracy of its description of the wave function needed for high-accuracy calculations. The advantage of this scheme is that integral evaluation can be completed more quickly. This is partly responsible for the popularity of the Pople basis sets described below. 

An older, but still used, notation specihes how many contractions are present. For example, the acronym TZV stands for triple-zeta valence, meaning that there are three valence contractions, such as in a 6—311G basis. The acronyms SZ and DZ stand for single zeta and double zeta, respectively. A P in this notation indicates the use of polarization functions. Since this notation has been used for describing a number of basis sets, the name of the set creator is usually included in the basis set name (i.e., Ahlrichs VDZ). If the author s name is not included, either the Dunning-Hay set is implied or the set that came with the software package being used is implied. 

Three such methods have been proposed by Morokuma and coworkers. The integrated MO + MM (IMOMM) method combines an orbital-based technique with an MM technique. The integrated MO + MO method (IMOMO) integrates two different orbital-based techniques. The our own n-layered integrated MO and MM method (ONIOM) allows for three or more different techniques to be used in successive layers. The acronym ONIOM is often used to refer to all three of these methods since it is a generalization of the technique. 

Note A few symbols are duplicated. Although this is at times confusing, it does reflect common usage in the literature. Thus, it is an important notation for the reader to understand. Acronyms are defined in the glossary at the end of the book. 

Among the complexing agents that find use as titrating agents, ethylenediamine-A,A(A, A-tet-raacetic acid (acronym EDTA, and equation abbreviation, H4Y) is by far the more important, and it is used in the vast majority of complexometric titrations. The successive acid values of H4Y are pKi = 2.0, pisTj = 2.67, = 6.16, pTCt = 10.26 at 20°C and an ionic strength of 0.1. The fraction... 

A big step forward came with the discovery that bombardment of a liquid target surface by abeam of fast atoms caused continuous desorption of ions that were characteristic of the liquid. Where this liquid consisted of a sample substance dissolved in a solvent of low volatility (a matrix), both positive and negative molecular or quasi-molecular ions characteristic of the sample were produced. The process quickly became known by the acronym FAB (fast-atom bombardment) and for its then-fabulous results on substances that had hitherto proved intractable. Later, it was found that a primary incident beam of fast ions could be used instead, and a more generally descriptive term, LSIMS (liquid secondary ion mass spectrometry) has come into use. However, note that purists still regard and refer to both FAB and LSIMS as simply facets of the original SIMS. In practice, any of the acronyms can be used, but FAB and LSIMS are more descriptive when referring to the primary atom or ion beam. 

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