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Item Metadata only Distorted wave theory of the 50 MeV (p, 2p) reaction(Elsevier, 1969) McCarthy, I.E.; Thomas, A.W.An attempt is made to answer the question whether distorting potentials that give really good fits to elastic scattering cross sections and total reaction cross sections for experiments in the relevant two-body subsystems can correctly give positions of maxima and minima in the (p, 2p) angular correlation. The 50 MeV energy range is chosen because the angular correlation is very sensitive to the distortion. It is found that the positions are correctly reproduced by good elastic scattering parameters for the reaction 89Y(p, 2p)88Sr, Q = 7.44 MeV, at 46 MeV. The shortcoming of the distorted wave theory at this energy, as at higher energies, is that the calculated ratio of the cross section at small angles to that at large angles is too large. Apart from this serious defect, the shape of the angular correlation for 12C(p, 2p)11B, Q = 16 MeV, at 50 MeV is also encouraging. Previous studies suggest that the defect can be corrected if a better description of the p-p t-matrix is used in the distorted wave theory.Item Metadata only The circular dichroism and the chirality of the unsymmetric-cis- and the trans-(+)D-bis(diethylenetriamine)cobalt(III) ion(Royal Society of Chemistry, 1970) Keene, F.R.; Searle, G.H.; Mason, S.F.The circular dichroism of the systems u-cis-(+)D-[Co(dien)2]3+ and trans-(+)D-[Co(dien)2]3+ indicates the stereochemical configuration of the former, and indicates in the latter a new type of chirality which has hitherto not been realized, but which will be present in metal–polyamine complexes.Item Metadata only Importance of the D-state probability of the deuteron in threshold p + p → π + d(American Physical Society, 1971) Thomas, A.W.; Afnan, I.R.Abstract not availableItem Metadata only Pion absorption and the pion-deuteron scattering length(Elsevier, 1973) Thomas, A.W.; Afnan, I.R.The solution of the Faddeev equation for the πNN system has been used as a model for studying pion absorption and elastic scattering on the deuteron. Results indicate that absorption is sensitive to the short range behaviour of the deuteron wave function. The contribution of absorption to the πd scattering length is found to be small.Item Metadata only Faddeev approach to pion production and pion-deuteron scattering(American Physical Society, 1974) Afnan, I.R.; Thomas, A.W.Abstract not availableItem Metadata only Charge symmetry as a constraint on off-shell effects in the three-nucleon system(Elsevier, 1975) Thomas, A.W.; Afnan, I.R.Abstract not availableItem Metadata only A three-body calculation of πd scattering(North-Holland Pubhshtng Co., 1976) Thomas, A.W.Abstract not availableItem Metadata only Photo-bisdecarbonylation. An entry into the highly reactive isobenzosystem: isoindene(Pergamon Press, 1977) Warrener, R.N.; Russell, R.A.; Lee, T.S.Abstract not availableItem Metadata only A photochemical route to spiro[2.8]undeca-2,4,6,8-tetraene (2-spirocyclopropylisoindene)(Pergamon Press, 1977) Warrener, R.N.; Harrison, P.A.; Russell, R.A.Abstract not availableItem Metadata only The rearrangement of vinyl epoxides derived from bicyclo[4.2.0]Octa-2,4,7-trienes(Pergamon Press, 1978) Warrener, R.N.; Russell, R.A.; Tan, R.Y.S.Abstract not availableItem Metadata only A theory of low energy pion-nucleus scattering(North-Holland Publishing Co., 1978) Landau, R.H.; Thomas, A.W.Abstract not availableItem Metadata only A comparative study of Jones's, Collins's and Corey's reagents in the chromium(VI) oxidation of an epimeric pair of allylic alcohols in the benzo-fused Norbornen-5-ol series(CSIRO Publishing, 1978) Warrener, R.N.; Lee, T.S.; Russell, R.A.; Paddon-Row, M.N.A comparison has been made between a series of chromium(VI) oxidizing agents, as well as manganese dioxide, a bicyclic allylic secondary alcohol, the exo-ol (7), being the substrate. Jones's, Collins's and Corey's reagents gave, in each case, a mixture of products: the main reactions were epoxidation to yield (8) and (9), normal ketone formation (10), and ring-fragmentation to form the indanol (11) and the indanone (12). All reagents yielded substantial amounts of epoxide, which is rare for Collins's reagent, and unprecedented for Corey's reagent, and varying amounts (13-30 %) of ketone, while Jones's reagent alone gave significant ring-opened products. A dramatic change in product composition was observed with the epimeric endo-alcohol (13), where Jones's reagent (only one studied) yielded the related α,β,-unsaturated ketone (10) in essentially quantitative yield. A discussion of these results is presented in terms of the current understanding of the mechanism of chromium oxidations.Item Metadata only Cycloaddition routes to polycyclic quinones: Part 1 boron triacetate as a regiochemical directing agent(Pergamon Press, 1979) Russell, R.A.; Collin, G.J.; Sterns, M.; Warrener, R.N.9-Hydroxy-1,4-anthraquinone, a benzannelated juglone derivative, undergoes regiospecific cycloaddition with isoprene when conducted in the presence of boron triacetate. The structure of this regiomer has been determined by X-ray crystallography.Item Metadata only The synthesis and photochemistry of bicyclo[4.2.0]octa-2,4,7-trienes(Pergamon Press, 1979) Warrener, R.N.; McCay, I.W.; Tan, R.Y.S.; Russell, R.A.Two new crystalline bicyclo[4.2.0]octa-2,4,7-trienes have been prepared by photodecarbonylation of the appropriate tricyclo[4.2.1.0²,⁵]nona-3,7-dien-9-ones and their structures confirmed by ¹³C-n.m.r. The title compounds all undergo thermal ring opening to cyclooctatetraenes, but photolysis is substituent dependent.Item Metadata only The application of ¹³C-N.M.R. spectroscopy to the determination of the stereochemistry of Diels-Alder adducts(Pergamon Press, 1979) Tan, R.Y.S.; Russell, R.A.; Warrener, R.N.Long-range (³J) ¹³C-H coupling is a reliable probe to evaluate the stereochemistry of cycloaddition products. The method is best applied to carbonyl containing adducts but not restricted to them. Several structures have been revised and new ones evaluated.Item Metadata only The stereochemistry of the adducts derived from the Diels-Alder addition of cyclobutenes and cyclopentadienones: a caveat on some existing PMR methods for the assignment of stereochemistry(Pergamon Press, 1979) Warrener, R.N.; Tan, R.Y.S.; Russell, R.A.The stereochemistry of the adducts formed from the cycloaddition of tetracyclone, phencyclone and 2-methyl-3,4,5-triphenylcyclopenta-2,4-dienone with cis-3,4-dichlorocyclobutene (in one case with 3-chloro-4-methoxycyclobutene) has been evaluated in a rigorous fashion. This allows a firmly-based caveat to be issued regarding the p.m.r. probe for stereochemical evaluation of tetracyclone adducts recently proposed by Coxon and Battiste.Item Metadata only The effect of genuine pion absorption and emission on πd scattering(Elsevier, 1979) Rinat, A.S.; Starkand, Y.; Hammel, E.; Thomas, A.W.Intermediate pion absorption and reemission through π and ϱ rescattering has been included in a computation of πd elastic cross sections and polarizations for pion energies through the resonance region. Appreciable effects are computed for these observables, notably for polarizations.Item Metadata only The case for studying the (π, πN) reaction in coincidence under optimum conditions(Elsevier B.V., 1979) Jackson, D.F.; Ioannides, A.A.; Thomas, A.W.Abstract not availableItem Metadata only Preparation of (–)-(7R)-7-acetyl-7-hydroxy-4,4-dimethoxy-5,6,7,8-tetrahydro-naphthalen-1(4H)-one, a chiral AB-synthon for anthracycline synthesis(Royal Society of Chemistry, 1981) Warrener, R.N.; Gee, P.S.; Russell, R.A.The (–)-(R)-dienone (13) was prepared in 10 steps from the known 8-hydroxy-5-methoxy-2, 3-dihydronaphthalen-1(4H)-one (2), and the chirality at C(7) in (13) corresponds to that found at C(9) in the naturally occurring anthracyclines related to daunomycin.Item Metadata only The regiospecific preparation of 1,4-dioxygenated anthraquinones: a new route to islandicin, digitopurpone, and madeirin(Royal Society of Chemistry, 1981) Russell, R.A.; Warrener, R.N.A direct, versatile, one-step synthesis of anthraquinones which exhibits total regioselectivity (>99%) and involves the reaction of the anion of 4- or 7-methoxy-3-phenylsulphonylphthalides with variously substituted quinone monoacetals is reported.