An experimental demonstration of winding number dependence of the Aharonov-Bohm effect

Measurements on a superconducting ring which twice encircles a long solenoid containing flux show quantized flux states with $\text{δφ =}\text{φ}{}_0\text{2}\text{=}\text{h}\text{4e}$. This explicity demonstrates the winding number dependence of the Aharonov-Bohm effect.     

Reactivity of (3-chloro-2-methylenecycloalkyl)palladium chloride dimers: pd-allyl cleavage,synthesis of (±)-13-methyltridecanolide.

The reactions of the title compounds under cleavage conditions affords the corresponding cycloalkenes as the major product. This methodology was used in the synthesis of 13-methyltridecanolide from cyclododecene.     

Self-focusing and the initial stages of plasma generation by short laser pulses

When a short high power laser pulse interacts with a transparent solid target in vacuum, radiation in the rising edge of the pulse can self-focus in the solid and cause “damage tracks”. The self-focusing stage of the laser/solid interaction has been studied, a method has been found to suppress the “damage tracks”, and information about the penetration of laser radiation through the critical layer of plasma, in the early stages of the interaction, has been obtained.     

Synthetic studies directed toward the proposed structure for heteroscyphic acid A

A route to the carbon skeleton of the proposed structure for heteroscyphic acid A was developed utilizing a Mn(III)/Cu(II) mediated oxidative free-radical cyclization and nucleophilic addition to (3-methylpentadienyl)iron(1+) cation.     

Crystal and molecular structure of a steroidal spirocyclic lactone, C29H34O4

The X-ray crystal structure of the title compound, as crystallized from methanol–methylene chloride was determined. The asymmetric unit contains two steroid molecules, which differ primarily in the orientation of the aromatic rings of the benzyl ethers. The title compound crystallizes in the noncentrosymmetric space group P2(1), with a = 7.558(2), b = 16.673(3), c = 18.735(4) Å, = 97.610(10)°, and D _calc = 1.268 g cm^–1 for Z = 4.     

Decongestion of methylene spectra in biological and non-biological systems using picosecond 2DIR spectroscopy measuring electron-vibration–vibration coupling

Methylene is found in the repeat units of many polymers including proteins. In some cases it appears to be a useful reporter of variation in local environment whilst in other contexts average behaviour seems to dominate. In this paper we apply a particular 2DIR technique to a range of systems containing methylene groups, showing that mode frequencies, linewidths and splittings can be easily extracted even when the infrared absorption bands are too congested to allow reliable analysis. 2DIR spectra of polyethylene and several liquid alkanes are compared and it is shown for the case of l-arginine that the methylene scissor modes are split and that this can be resolved by tracking the 2DIR spectrum as a function of time. Calculations from first principles reveal that for most of the methylene modes studied, electrical anharmonicity is the dominant contributor to the 2DIR cross-peak intensity, with the mechanical anharmonicity making only a small contribution.