Proton implantation-induced intermixing of InAs quantum dots QDs capped with InP, GaInAsP, and InP and InGaAs layers grown by metal-organic chemical vapor deposition is investigated. The samples are annealed at 750, 800, 850, and 900 °C for 30 s and thermal stability of the QDs is studied. The optimum annealing temperature is around 800 °C which gives maximum implantation-induced energy shift. ...

2,2,6,6-Tetramethylpiperidinyl-masked 1,2-diols exhibited stereochemistry-dependent hydroxyl proton chemical shifts: ca. 7 ppm for the syn diastereomer and ca. 2 ppm for the anti diastereomer. A computational search for low energy geometries revealed that the syn isomer favors a six-membered ring hydrogen bond to nitrogen and the anti isomer favors a five-membered ring hydrogen bond to oxygen. ...

The dependence of amide proton chemical shifts on temperature is used as an indication of the hydrogen bonding properties in a protein. The amide proton temperature coefficients of the beta-helical antifreeze protein from Tenebrio molitor are examined to determine their hydrogen bonding state in solution. The temperature-dependent chemical shift behavior of the amides in T. molitor antifreeze p...

BIRD's eye view: Adding periodic BIRD J-refocusing (BIRD=bilinear rotation decoupling) to data acquisition in an HSQC experiment causes broadband homonuclear decoupling, giving a single signal for each proton chemical shift. This pure shift method improves both resolution and signal-to-noise ratio, without the need for special data processing.

The downfield shift of the tyrosyl proton resonances and an increased chemical shift difference between the resonances for the 2',6' and 3',5' hydrogens in a series of deamino-oxytocin analogs modified in the disulfide bridge provide evidence for aromatic-sulfur interactions in d6-dimethylsulfoxide solutions.

A combined and sequential use of Monte Carlo simulations and quantum mechanical calculations is made to analyze the spectral shift of the lowest pi-pi* transition of phenol in water. The solute polarization is included using electrostatic embedded calculations at the MP2/aug-cc-pVDZ level giving a dipole moment of 2.25 D, corresponding to an increase of 76% compared to the calculated gas-phase ...