Chandrasekhar studies

Most of the other compounds that have been studied usually have an oligomethylene bridge and have been studied by Dakternieks s group. They give tetradistannoxanes by intramolecular association examples of these compounds are given in Table 6, and more are to be found in Chandrasekhar s review.347... 

Cyclopentyl isoxazolidine cycloadduct 324 was prepared by intramolecular nitrone cycloaddition by Baldwin et al. (280,281,352,353) as part of studies toward a total synthesis of pretazettine (Scheme 1.69). Related adducts have been prepared elsewhere (354—356) including fluorine-substituted carbocycles (357) and the adducts prepared by lOAC by Shipman and co-workers (333,334) who demonstrated their potential as a route to aminocyclopentitols (Scheme 1.66, Section 1.11.2). Such bicyclic structures have been prepared in rather unique intermolecular fashion by Chandrasekhar and co-workers (357a) from the cycloaddition of C,N-diphenyl nitrone to fulvene (325). 

A. Rathna and J. Chandrasekhar, Theoretical study of hydrogenated Buckminster-fullerene derivatives with benzenoid rings, Co0Ho0-On (n = 1-8), Chem. Phys. Lett. 206, 217-223(1993). 

Kattumuri V, Katti K, Bhaskaran S, Boote EJ, Casteel SW, Eent GM, Robertson DJ, Chandrasekhar M, Kannan R, Katti KV. Gum arabic as a phytochemical construct for the stabilization of gold nanoparticles in vivo pharmacokinetics and x-ray-contrast-imaging studies. Small 2007 3 333-341. 

Chandrasekhar, S., Mohapatra, S., Lakshman, S. Study of Bamford-Stevens reaction on a-oxy tosyihydrazones. Chem. Lett. 1996, 211-... 

Chandrasekhar, S., 1939, Introduction to the Study of Stellar Structure, University Press, Chicago... 

W.J. Hehre, R. Ditchfield, J.A. Pople, Self—Consistent Molecular Orbital Methods. Xll. Further Extensions of Gaussian—Type Basis Sets for Use in Molecular Orbital Studies of Organic Molecules, J. Chem. Phys. 56 (1972) 2257 T. Qark, J. Chandrasekhar, P.V.R. Schleyer, Efficient diffuse function-augmented basis sets for anion calculations. 111. The 3-21+G basis set for flrst-row elements, Li-F, J. Comput. Chem. 4 (1983) 294. 

In the p3/2 Ga spectrum of Fig. 7.3, an anomalous broadening of line 2(Ga) is observed, together with a rather sharp, but weak X feature near from the energy of the O(r) phonon in silicon. This feature is attributed to a splitting of line 2 due to the interaction with the O(r) phonon. This resonant interaction has been further studied under uniaxial stress by Chandrasekhar et al. [34]. The X feature is seen to be split by stress and its relative sharpness at zero stress is attributed to its interaction with phonons close to the q = 0 T point while line 2 interacts with a larger phonon distribution. 

Following an earlier qualitative prediction that para-disilabenzene 93 and the corresponding Dewar structure 94 should be close in energy245, Chandrasekhar and Schleyer250 studied this system using the 3-21G( V/STO-3G level of theory. In addition to 94 the isomeric silylenes 95 and 96 were also studied. 

UCo is a paramagnet with a weakly temperature-dependent exchange-enhanced magnetic susceptibility of 0.93 X 10 8 m3/mol at 300 K that increases by less than 2% when cooling to 1.6 K (Chen et al. 1985). The originally reported superconductivity below 1.7 K (Chandrasekhar and Hulm 1958) was recently studied in more detail by Chen et al. (1985) who found Tc = 1.22 K and a critical field Ha = 1.7 T (extrapolated to 0 K). This compound represents an example of a regular U superconductor in the sense of the Hill plot because dv v 320 pm. Also the low value of y = 7.84 mJ/mol K2 is consistent with this picture. Compared to the other U-based superconductors (Meisner et al. 1984), UCo exhibits the highest Stoner enhancement parameter, S = 7. This can be correlated with the spin-fluctuation... 

Discotic liquid crystals came to prominence in the late 1970s when Chandrasekhar, Sadashiva, and Suresh reported the discovery of this new class of liquid-crystalline molecules, which were found to form columnar phases. The first of these, a hexaalkanoate of benzene, is shown in Figure 9. There then followed a rather unfortunate confusion of nomenclature in which the phases formed by discotic molecules were themselves referred to as discotic, carrying the abbreviation D. A liquid-crystal phase must be characterized by its symmetry and organization and not the shape of the molecules of which it is composed this is particularly important in columnar systems as many non-discotic molecules exhibit columnar phases. Indeed, columnar mesophases have been recognized for many years and studies date back to at least the 1960s with the work of Skoulios with various metal soaps. " Therefore, columnar phases take the abbreviation Col followed by some descriptor that describes the symmetry of the phase. 

V. Kattumuri, K. Katti, S. Bhaskaran, E. J. Boote, S. W. Casteel, G. M. Pent, D. J. Robertson, M. Chandrasekhar, R. Kannan, and K. V. Katti, Gum arabie as a phytochemieal eonstruet for die stabilization of gold nanopartieles In vivo pharmacokinetics and X-ray-conlrast-imaging studies. Small, 3 (2007) 333-341. 

For a review of experimental studies on dielectric dispersion, see S. Chandrasekhar and N. V. Madhusudana, in Topics in Molecular Interactions (ed. W. J. Orville-Thomas, H. Ratajezak and C. N. R. Rao), Elsevier, Amsterdam and Indian Academy of Sciences, Bangalore, p. 139 (1985). 

For a full list of references to dielectric studies on strongly polar materials see S. Chandrasekhar, Plenary Lecture at the Tenth International Liquid Crystal Conference, York, July 15-21, 1984 Mol. Cryst. Liquid Cryst.,... 

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