Study of structural and electronic transport properties of Ce-doped LaMnO3

The structural and electronic transport properties of La_1−x Ce _x MnO₃ (x=0.0–1.0) have been studied. All the samples exhibit orthorhombic crystal symmetry and the unit cell volume decreases with Ce doping. They also make a metal-insulator transition (MIT) and transition temperature increases with increase in Ce concentration up to 50% doping. The system La_0.5Ce_0.5MnO₃ also exhibits MIT instead of charge-ordered state as observed in the hole doped systems of the same composition.     

Generics for computable Mathias forcing

We study the complexity of generic reals for computable Mathias forcing in the context of computability theory. The n-generics and weak n-generics form a strict hierarchy under Turing reducibility, as in the case of Cohen forcing. We analyze the complexity of the Mathias forcing relation, and show that if G is any n  -generic with n≥2$n\ge 2$ then it satisfies the jump property G⁽ⁿ⁻¹⁾_≡TG^′⊕∅⁽ⁿ⁾$G^{(n-1)}{\equiv }_T{G}^{\prime }\oplus {\varnothing }^{(n)}$. We prove that every such G has generalized high Turing degree, and so cannot have even Cohen 1-generic degree. On the other hand, we show that every Mathias n-generic real computes a Cohen n-generic real.     

Molecular Compton profiles from SCF-MO wavefunctions

Compton profiles are derived from ab initio SCF-MO wavefunctions calculated for cyclopropane, propene, aziridine, ethanimine, ethenamine, oxirane, acetaldehyde and formamide using Dunning's gaussian orbital basis. Good agreement with the experimental profile is found for formamide. The differences between the profiles for the cyclic and acyclic isomers are only slightly larger than the experimental accuracy that can presently be achieved. The cyclic compounds have slightly broader profiles and there are no significant differences arising from strain. Comparison with profiles derived from localized orbital contributions indicate that the localized orbital approach is essentially valid for these systems.     

Structure of actin cross-linked with alpha-actinin: a network of bundles

Three-dimensional laser scanning confocal microscopy has revealed that filamentous actin, when complexed with the cross-linking protein alpha-actinin, will spontaneously assemble on a micron scale into a structure comprised of a relatively rigid, frequently branching, 3D network of bundles with characteristic mesh size of the order of the persistence length of F-actin. In contrast, additional nanoscale ordering is observed, as synchrotron x-ray diffraction has revealed a disordered, distorted square lattice of actin fibers within the individual bundles.     

Interactions between a 3d impurity and conduction electrons

We calculate the effective interaction between a 3d impurity and conduction electrons resulting from an Anderson mixing interaction taken to second order. The orbital state of the impurity in the crystal field is taken into account. The results, which are tabulated in detail, exhibit coupling of the conduction electrons to the impurity's orbital degrees of freedom as well as to its spin.     

Computational screening of combinatorial catalyst libraries

A catalyst design methodology, utilizing combinatorial synthesis in parallel with chemometric analysis, is presented, which considers the 3D steric and electrostatic properties of substituents about a constant core structure.     

Calculation of 14N hyperfine coupling constants by the INDO-MO method

The proportionality constant between the hyperfine splitting constant for ¹⁴N and the spin density calculated by the INDO-MO method has been redetermined using a larger sample of results. A revised value of 332 Gauss is suggested.     

Controlling the materials properties and nanostructure of a single-component dendritic gel by adding a second component

This paper reports a dendritic system which is capable of forming both one-component and two-component gels--interestingly the addition of the second component can either increase or decrease the degree of gelation, depending on dendritic generation.