Kerr constant of water from 280 to 350 K at 632.8 nm

The Kerr constant (B_T) of deionized liquid water was measured in the temperature range from 280 K to 350 K using 2 μs duration electric pulse fields up to 50 kV cm^?1. The value of B_T has been determined as 2.92 × 10^?14 mV^?2 at 298 K. Results indicate a steady decrease in the value of the Kerr constant with the rise of temperature.     

Designing New Materials Using Atomic Clusters

Designing principles for forming stable metallic clusters whose chemistry mimics different atoms of the periodic table are discussed. It is shown that while bulk Al is a metal, the chemistry of an Al₁₃ resembles that of a halogen atom, a CAl₁₂ resembles an inert atom, while a NAl₁₂ resembles an alkali atom. The feasibility of making new materials using clusters as the building blocks is discussed. An ionic solid made out of Al₁₃ (or BAl₁₂) and Cs is shown to be metastable and marked by a large gap at the Fermi energy even though bulk Al and Cs are metals.     

Rings, towers, cages of ZnO

Theoretical electronic structure studies on (ZnO)_n (n= 2–18, 21) have been carried out to show that the transition from an elementary ZnO molecule to the bulk wurtzite ZnO proceeds via hollow rings, towers, and cages. Our first principles electronic structure calculations carried out within a gradient corrected density functional framework show that small Zn_nO_n (n=2–7) clusters form single, highly stable rings. Zn₃O₃ and the symmetric cage Zn₁₂O₁₂ are shown to be particularly stable clusters. Among larger clusters, the most stable are oblong cages, Zn₁₅O₁₅, Zn₁₈O₁₈, and Zn₂₁O₂₁, which are reminiscent of nanotubes.     

An anomaly in the isotopomer shift of the hyperfine spectrum of LiI

A high-precision examination of the hyperfine spectrum of 6LiI in comparison with 7LiI shows a shift in the iodine nuclear electric quadrupole moment that cannot be accounted for by a model in which the electric field gradient at the iodine site is assumed to depend only upon the internuclear distance between Li and I. The other hyperfine interactions are consistent between the two isotopomers, including the previously reported electric hexadecapole interaction of the iodine nucleus.     

Absence of preclassical solutions in Bianchi I loop quantum cosmology

Loop quantum cosmology, the symmetry reduction of quantum geometry for the study of various cosmological situations, leads to a difference equation for its quantum evolution equation. To ensure that solutions of this equation act in the expected classical manner far from singularities, additional restrictions are imposed on the solution. In this Letter, we consider the Bianchi I model, both the vacuum case and the addition of a cosmological constant, and show using generating function techniques that only the zero solution satisfies these constraints. This implies either that there are technical difficulties with the current method of quantizing the evolution equation, or else loop quantum gravity imposes strong restrictions on the physically allowed solutions.     

Baryon magnetic moments in quark-diquark model

The baryon magnetic moments in quark-diquark model are studied and it is found that the diquark (spin 1 and 0) mixing which may arise as a result of quarkgluon interaction inside a hadron, leads to a good agreement of theory with experiment.     

Radical nucleophilic substitution mechanism in the reactions of arenediazonium cations with nitrite ion

Reactions of arenediazonium cations with nitrite ion generally believed to involve nucleophilic displacement have been found to occur via single electron transfer where free radicals intervene.     

Structure factor for a Bose fluid

The structure factor is calculated for a Bose fluid using an expression for S(k), which is approximately valid for all values of k. Marked fluctuations appear for $\text{k = 2.15}\text{A}\text{?}{}^{-1}$, near the roton dip in E_k, and at $\text{k = 3.65}\text{A}\text{?}{}^{-1}$ near the dip in the second branch of E_k. Our calculations are indirectly a theoretical justification for the existence of a second branch in E_k. The results presented here agree fairly well with the experimental values for $\text{k >; 3.0}\text{A}\text{?}{}^{-1}$ along with a dip at $\text{k = 3.67}\text{A}\text{?}{}^{-1}$ which has not been reported earlier. It also suggests the existence of two waves, phonons and rotons, for $\text{k >; 3.0}\text{A}\text{?}{}^{-1}$.