Thornton effect

The effect of making X more electron withdrawing is to stabilize the complexes in the corners B and D relative to A and C. As a result the transition state is shifted towards corner A ("Hammond effect") and toward corner B ("Thornton effect") as shown in Fig. lb. The net result of the two effects is to shift the transition state in the direction of more proton transfer and a should increase. This is again borne out by the results a similar trend in a was found for the phenoxide ion departure from substituted benzaldehyde methyl phenyl acetals (13). 

D.W. Hoffman, J.A. Thornton, Effects of Substrate Orientation and Rotation on the Internal Stresses in Sputtered Metal Films, J. Vac. Sci. Technol. 16 (1979) 134. 

Kaplan and Thornton (1967) determined secondary kinetic isotope effects in two 8 2 displacement reactions, one of which involved quatemi-zation of N,N-dimethylaniline and N,N-dimethyl-eig-aniline with methyl p-toluenesulphonate (CHgOTs). The reactions were carried out in... 

Changes in observed CH (CD) stretching frequencies on going from reactant to product are found to be too small and in the wrong direction to account for the observed kinetic isotope effect, and the effect is suggested to be due to increased force constants for lower frequency vibrations, such as for bending (Kaplan and Thornton, 1967). This is consistent with a steric explanation. 

A recent paper by Leffek and Matheson (1971) nicely complements this work, as it describes the results of a careful investigation of the temperature dependence of the kinetic isotope effect in the reaction studied by Kaplan and Thornton (1967). It is found that AAH = 134 + 30 cal mol and dd/S = 0-15 + 0-09 cal mol deg , demonstrating that the isotope effect is primarily due to an enthalpy difference, and providing support for the steric interpretation suggested by Kaplan and Thornton (1967). 

Cooke, A. (1988). Poisoning of woodpigeons on Woodwalton fen. M.P. Greaves, B.D. Smith, and P.W. Greig-Smith (Eds.) Field Studies for the Study of the Environmental Effects of Pesticides. BCPC Monograph No. 40, Thornton Heath, U.K. British Crop Protection Council, 297-301. 

It is likely that of the vast array of compounds released by plant roots, very few have a direct effect on the growth of soil-grown plants. One must ask whether they serve any useful purpose at all. The fears and uncertainty about what is physiologically normal were expressed by Ayers and Thornton in 1968 (97) their... 

The ability of STM to image at the atomic scale is particularly exemplified by the two other chapters in the book. Thornton and Pang discuss the identification of point defects at Ti02 surfaces, a material that has played an important role in model catalyst studies to date. Point defects have been suggested to be responsible for much of the activity at oxide surfaces and the ability to identify these features and track their reactions with such species as oxygen and water represents a major advance in our ability to explore surface reactions. Meanwhile, Baddeley and Richardson concentrate on the effects of chirality at surfaces, and on the important field of surface chirality and its effects on adsorption, in a chapter that touches on one of the fundamental questions in the whole of science - the origins of life itself ... 

Turowski, M., Yamakawa, N., Meller, J., Kimata, K., Ikegami, T., Hosoya, K., Tanaka, N., Thornton, E.R. (2003). Deuterium isotope effects onhydrophobic interactions, the importance of dispersion interactions in the hydrophobic phase. J. Am. Chem. Soc. 125, 13836-13849. 

Brereton, A., H. Lord, I. Thornton, and J.S. Webb. 1973. Effect of zinc on growth and development of larvae of the Pacific oyster Crassostrea gigas. Mar. Biol. 19 96-101. 

Thornton, I. and M. Farago. 1997. The geochemistry of arsenic. Pages 1-16 in C.O. Abernathy, R.L. Calderon, and W.R. Chappell (eds.). Arsenic. Exposure and Health Effects. Chapman Hall, London. 

Spence MJ, Bottrell SH, Thornton SI, Richnow HH, Spence KH (2005) Hydrochemical and isotopic effects associated with petroleum fuel biodegradation pathways in a chalk aquifer. J Con... 

Fraga, S. and Thornton, S. E. Theoretical studies of peptidic structures. Environmental effects, Theor. 

THORNTON, J. D. Trans. Inst. Chem. Eng. 35 (1957) 316. Liquid-liquid extraction. Part XIII. The effect of pulse wave-form and plate geometry on the performance and throughput of a pulsed column. 

Swain, C.G. and Thornton, E.R. Initial-state and transition-state isotope effects of methyl halides in light and heavy water, J. Am. Chem. Soc., 84(5) 822-826, 1962. 

Thornton, M. K., Lewis, M. D., Barta, J. L., Kleinkopf, G. E. (1994). Effect of nitrogen management on Russet Burbank tuber dormancy and response to CIPC. American Potato Journal, 71, 705. 

Hodson, M. E., Valsami-Jones, E., Cotter-Howells, J. D., Dubbin, W. E., Kemp, A. J., Thornton, I. Warren, A. 2001. Effect of bone meal (calcium phosphate) amendments on metal release from contaminated soils - a leaching column study. Environmental Pollution, 112, 233-243. 

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