Other NIST Databases

NIST currently offers five databases for applications in surface and interface science [7] see also Note. These databases are intended principally for use with AES and XPS, but they are also useful for other surface-sensitive spectroscopies in which electron beams are employed, for other analytical applications such as electron-probe microanalysis and analytical electron microscopy, and for other purposes such as electron-beam lithography and radiation physics. The five databases are as follows  

The XPS database is available on the internet [96], while the other databases operate on personal computers (PCs). Four extensive review articles have been published that discuss the relevant concepts, theoretical and experimental methods, and data reliability for SRD 64 [97, 98], SRD 71 [49], and SRD 82 [48]. SRD 20 is described on its web site [96], and information on SRD 100 has been published [99, 100]. 

Examples of data from SRD 71 and SRD 82 have been presented in earlier sections of this chapter. We now give information on the other three databases and show examples of data from these sources. 

2 NIST Electron Elastic-Scattering Cross-Section Database (SRD 64) 

Knowledge of elastic-scattering effects is important in the development of models for quantitative AES, XPS, and other techniques. Analytical descriptions of electron transport for AES and XPS have been developed on the basis of the transport approximation, as described earher. It is clear from the right-hand side of Eq. 

---

SRD 71 [68] and SRD 82 [41], provide convenient data for IMFPs, EALs, and MEDs. Other NIST databases and software from various sources provide simulations of spectra for thin-film samples [95], reference data needed for modeling the transport of signal electrons in different materials [35], chemical-state information [96], instrumental calibration [118], identification of sample morphology [124], and spectrum-analysis tools. 

In 1965, Adams et al. [62] obtained the absolute rate constants for the reaction of OH with a number of solutes, using the competition method the reactions of OH with C03, SCN , and Se03 that give the absorbing radicals C03 ", (SCN)2" and Se03 , respectively, were used as references. Similarly, Thomas [63] determined the rate constant for the reaction of OH with 1 by following the formation of l2 (2max 385 nm, max 940 m moF ) [56], and from that derived the rate constants for other reactions of the OH radical [63]. The NDRL/NIST Database cited above contains 1787, 715, and 171 entries for the reactions of OH, H , and 0 , respectively [7a]. 

For example, two comprehensive databases, ICSD and CSD, contain crystallographic data and structural information about inorganic, and organic and metal organic compounds, respectively, while NIST database encompasses all types of compounds but provides only crystal data with references. Other databases are dedicated to specific classes of materials, such as metals and alloys, proteins and macromolecules, minerals or zeolites. Search-match utilities are usually provided with databases or they may be obtained separately. 

For high-temperature liquids, compressed gases, and other systems at intermediate densities, a corresponding-states treatment is preferable. The SUPERTRAPP model for thermal conductivity is similar to that described for viscosity in Section 1.5.2, and is available in the same NIST databases [9, 59],... 

Other publications, however, report more accurate values of B3LYP gas phase Gibbs free energy calculations on aliphatic amines, diamines, and aminoamines. In 2007 Bryantsev et al. reported that B3LYP calculations with the basis set 6-31-h-G had a mean absolute error of 0.78 kcal/mol from experimental values of the gas phase basicity (AGg s) of the reverse reaction of equation 1 reported in the NIST database [58]. This accuracy is comparable to that of expensive, high level model chemistries, but because the experimental values have uncertainties of 2 kcal/mol, it is difficult to discern exactly how accurate the calculations are in comparison to values in the other publications [81]. The take-home message remains the same always benchmark DFT calculations for the systems you are interested in computing [52]. 

The pdf files in the Internet version of the Handbook mimic the new layout of the pages in the print edition. Furthermore, the number of interactive tables has been increased from 76 to 103. Among the topics included for the first time in interactive form are vapor pressure of the elements at high temperature heat of dilution and molar conductivity of acids electron and proton affinities atomic transition probabilities speed of sound in various media the NIST thermocouple tables and many others. The database from which these interactive tables are generated now has over 106,000 records which can be searched, manipulated, and displayed in a variety of ways. 

Molecular adiabatic ionization energies are to be found in the NIST database (see Further reading section) and other reference books. 

Although AES and XPS are widely regarded as mature surface-analytical tools, their applications are extremely varied and there can be many challenges to obtaining reliable information on the sample or process of interest We have presented information on data resources for AES and XPS with emphasis on databases available from NIST and information to determine the surface sensitivity of AES and XPS measurements. The key material parameter is the IMFP. Owing to elastic scattering of the signal electrons, other parameters needed for particular applications (the EAL for film-thickness measurements and quantitative analyses and the MED and ID for statements of surface sensitivity) need to be determined for the particular samples and conditions of measurement. Two NIST databases,... 

Reliable tables that list many known surface stmetures can be found in [1]. Also, the National Institute of Standards and Teclmology (NIST) maintains databases of surface stmetures and other surface-related infonnation, which can be found at httpsov/srd/surface. htm. 

Data for other substances can be obtained from the following critical compilations and online in the NIST Chemistry WebBook at http //www.webbook.nist.gov/ chemistry/ or from the NIST-TRC Databases available on disk. (Information can be found at http //www.nist.gov/srd/thermo.htm, or at http //srdata.nist.gov/ gateway/gateway keyword = thermodynamics.) An exhaustive list of earlier sources of tabulated thermochemical data can be found in Volume 1 of Chemical Thermodynamics, A Specialist Periodical Report [2]. A useful list of websites containing thermodynamic data is available at http //tigger.uic.edu/ mansoori/ Thermodynamic.Data. and.Property.html. 

In the case where MS analytical data has been contributed in the other formats, it is prepared into a NIST MS Database, using the NIST MS Search program. This program is used to create MS spectral files from the following electronic formats JCAMP, NIST ASCH, AMDIS, and NIST MS Database. If the analytical data contains no chemical structure, the structure is created in ISIS Draw and then imported into the database as an MOL file. The information associated with the MS analytical data is handled by the NIST program. 

The final PDF files of all the four analytical techniques, the NIST MS Database (MS only), the excel spreadsheet that indexes all the data (PDFIndex) that is on the CD-ROM, and the HTML browser are all included on the CD-ROM. The certificates from OIO are also included on the CD-ROM as PDF. The PDFIndex, NIST MS Database, and other utilities are hyperlinked to the HTML page. The analytical data presented in the excel spreadsheet (PDFIndex) are all hyperlinked to the individual PDF files and electronic MS files (refer to Table 2). The MS data in the NIST MS Database is hyperlinked via NIST links. All these files are put together and written onto a CD-ROM. The resulting CD-ROM is selfinstalling and automatically launches an HTML browser that allows the user to access analytical data and information on the CD-ROM from the browser. 

Tel. 301-975-2208, fax 301-926-0416, e-mail rdj3 enh.nist.gov Thermodynamic data for almost 5000 gas phase compounds. Estimations of structures drawn into program using Benson s additivity rules. IVTAN-TFIERMO database with enthalpies of formation and other thermodynamic properties for 2300 substances. PCs. 

The discovery in 1962 of the intense absorption band of eaq (Amax 720 nm, Cmax 1900 m mor ) [56] in pulse radiolysis experiments on aqueous solutions was made almost simultaneously at Mount Vernon Hospital [57] and Manchester [58], and provided an extremely useful method for measuring the rate constants for the reaction of this species with a variety of compounds. As mentioned in the Introduction, reactions of the hydrated electron are electron-transfer reactions. The first paper dealing with this type of measurement appeared in 1963 [59] and contained the rate constants for the reactions of Caq with H, H2O2, and O2. Many other rate constants for the reactions of Caq were determined in the following years. The NDRL/ NIST Solution Kinetics Database, Version 3, which covers the literature up to 1994, contains nearly two thousand entries for this type of reaction, almost all of them obtained by means of pulse radiolysis [7a]. In many cases, the rate constant for a given reaction has been determined more than once for example, the rate constants for the reaction of Caq with H+, NOs , C6H5NO2, Ag+, Cu +, and MV + (l,l -dimethyl-4,4 -bipyridinium) have been determined 19, 16, 14, 11, 10, and 8 times, respectively [7a]. 

For compounds that appear in Table 2-184, values are from E. W Lemmon, M. O. McLinden, and D. G. Friend, Thermophysical Properties of Fluid Systems in NIST Chemistry WebBook, NIST Standard Reference Database Number 69, Eds. P. J. Linstrom and W. G. Mallard, June 2005, National Institute of Standards and Technology, Gaithersburg, Md. (http //webbook.nist.gov). Values for other compounds are from International Critical Tables, vol. 5, pp. 80-82. 

---