SERS—Theory

The transition polarizability a can also be enhanced as a result of electronic interaction between the adsorbate and the metal. The most significant mechanism that produces an increase in the apparent value of a involves charge transfer between the metal and the adsorbate. Creighton (1986) has given a very illustrative example how charge transfer may occur from the metal to the adsorbate, which we will describe in the following. 

A third way (Creighton, 1988) in which the surface may modify the intensity of Raman scattering by molecules adsorbed at the surface is by perturbing the molecules as a result of the bonding interaction with the surface. However, it turned out that this chemical effect on the Raman spectra is relatively small, and it is not normally considered to be a part of SERS, though it is inseparable from it. Several other SERS mechanisms have also been proposed (see for instance the discussion by Moskovits, 1985) which by now are widely thought to make at most only minor contributions to the enhancements observed in SERS. 

By the two strong-enhancement mechanisms as discussed above a number of features inherent in SERS can now be understood. They have been summarized by Creighton (1990). Finally, we notice that the selection rules for SERS are fundamentally the same 

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N. Valley, N. Greeneltch, R.P. Van Duyne, G.C. Schatz, A look at the origin and magnimde of the chemical contribution to the enhancement mechanism of surface-enhanced Raman spectroscopy (SERS) theory and experiment. J. Phys. Chem. Lett. 4, 2599 (2013)... 

Quack M 1992 Time dependent intramolecular quantum dynamics from high resolution spectroscopy and laser chemistry Time Dependent Quantum Molecular Dynamics Experiment and Theory. Proc. NATO ARW 019/92 (NATO ASI Ser. Vol 299) ed J Broeckhove and L Lathouwers (New York Plenum) pp 293-310... 

K. Cohen, The Theory of Isotope Separation as Applied to the Targe-Scale Production oflJ-235 Nad. Nuclear Energy Ser. Div. Ill, Vol. IB, McGraw-HiU Book Co., New York, 1951, Chapt. 6. 

Foam Drainage and Overflow The rate of foam overflow on a gas-free basis (i.e., the total volumetric foamate rate Q) can be estimated from a detailed theoiy for foam drainage [Leonard and Lemlich, Am. Jn.st. Chem. Eng. J., 11, 18 (1965)]. From the resulting relationship for overflow [Fanlo and Lemlich, Am. Jn.st. Chem. Eng. Symp. Ser, 9, 75, 35 (1965)], Eq. (22-55) can be employed as a convenient approximation to the theory so as to avoid tri and error over the usual range of interest for foam of low hquid content ascending in plug flow ... 

This book is divided into five parts the problem, accidents, health risk, hazard risk, and hazard risk analysis. Part 1, an introduction to HS AM, presents legal considerations, emergency planning, and emergency response. This Part basically ser es as an oveiwiew to the more teclmical topics covered in the remainder of the book. Part 11 treats the broad subject of accidents, discussing fires, explosions and other accidents. The chapters in Parts 111 and Part IV provide introductory material to health and hazard risk assessment, respectively. Pai1 V examines hazaid risk analysis in significant detail. The thiee chapters in this final part include material on fundamentals of applicable statistics theory, and the applications and calculations of risk analysis for real systems. 

BenE74 Bender, E. A., Canfield, E. R. The asymptotic number of labelled graphs with given degree sequence. J. Combinatorial Theory Ser. A 24 (1978) 296-307. 

P.N. D yachkov, A.A. Levin, Vibronic theory of relative stability isomers in inorganic molecules and complexes, Itogy Nauki i tekhniki, ser. Stroenie molecul i khimicheskaya svyas, 11 (1987) (in Russian). 

M. L. Bernard et al, CRAcadSci, Ser C, 272 (26), 2112-15 (1972) CA.75, 101675 (1971) A generalization of the previously described (Bernard et al, 1971) ablation theory (for AP) combustion to include AP-based solid propints provides satisfactory fits to the exptl data of M. Summerfield et al (1960), with reproduction of the two distinct pressure regimes observed in the combustion of AP-based powders between 0 and 100 bars. The solid binding agent is assumed to be easily pyrolyzable, with each mol producing several combustible gaseous mols, as in the case of pyrolytically degrading polymers... 

Transition state theory, 46,208 Transmission factor, 42,44-46,45 Triosephosphate isomerase, 210 Trypsin, 170. See also Trypsin enzyme family active site of, 181 activity of, steric effects on, 210 potential surfaces for, 180 Ser 195-His 57 proton transfer in, 146, 147 specificity of, 171 transition state of, 226 Trypsin enzyme family, catalysis of amide hydrolysis, 170-171. See also Chymotrypsin Elastase Thrombin Trypsin Plasmin Tryptophan, structure of, 110... 

According to Anh s theory, the cyclopentadienes having snbstitutents of second and third row elements such as SR and SeR at the 5-positions are expected to react with syn n facial selectivity since the stabilization dne to n-jt interaction in such systems is larger than 1. The observation contradicted the prediction [3,4,7]. We and Ohwada... 

R.S. Rivlin, Large elastic deformations of isotropic materials. IV. Further developments of the general theory, Philos. Trans. R. Soc. (London) Ser. A, 241, 379-397, 1948. 

Optical Methods Reflectance and ellipsometry snffer from lack of a theory at the molecnlar level. The same is true for SERS and SHG. The main advances will be in the nse of far-IR spectroscopy and SFG. SFG measurements performed with femtosecond lasers open np new possibilities for time-resolved adsorbate stndies. 

Smart, DJ. and Humphreys, C.J. (1978) The crystal potential in electron diffraction and in band theory, Inst. Phys. Confs. Ser., 41, 145-149. 

Bernath, L., 1960, A Theory of Local Boiling Burnout and Its Application to Existing Data, Chem Eng. Prog, Symp. Ser. 56(30) 95- 116. (2)... 

Introduction to intersection theory in algebraic geometry, CBMS Regional Conf. Ser. in Math. vol. 44, AMS, Providence, R. I., 1984. 

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