Rapid mixing of substrate-free ferric cytochrome P450(BM3)-F87G with m-chloroperoxybenzoic acid (mCPBA) resulted in the sequential formation of two high-valent intermediates. The first was spectrally similar to compound I species reported previously for P450(CAM) and CYP 119 using mCPBA as an oxidant, and it featured a low intensity Soret absorption band characterized by shoulder at 370nm. This...

Excitation of HbCO by a single 6-psec 530-nm pulse results in photodissociation with a first-order constant of 0.89 X 10(11) sec-1. The kinetics of photodissociation, monitored by following absorbance changes in the Soret band at 440 nm, are interpreted as corresponding to predissociation followed by a corssing into a dissociative state. Subsequent recombination of CO with the porphyrin system ...

Soret resonance and Q, preresonance Raman spectra are reported and compared for a series of (bacterio)chlorophylIs. Chlorophyll a, 2-acetylchlorophyll a, bacteriochlorophyll a and 2-vinylbacteriochlorophyll a were studied in the non-protic solvent tetrahydrofuran. These experiments were designed to identify Raman bands corresponding to the stretching mode@) of the vinyl group at the C-2 positio...

The structural properties and absorption spectra of H2Pc thin films have been studied. The films used in these studies were thermally evaporated on glass/quartz substrates with thickness ranging from 60 to 460 nm. The XRD studies of H2Pc thin films showed that the as-deposited films have α-form with monoclinic system. The mean crystallite size (L), the dislocation density (δ) and the strain (ξ)...

Applying nonadiabatic excited-state molecular dynamics, we investigate excitation energy transfer and exciton localization dynamics in a chlorophyll a (Chla) dimer system at the interface of two monomers of light-harvesting complex II trimer. After its optical excitation at the red edge of the Soret (B) band, the Chla dimer experiences an ultrafast intra- and intermolecular nonradiative relaxat...

I. T. OLIVER AND W. A. RAWLINSON I955 the effect of the free aldehyde group. The Soret band of the oxime of the copper complex, in addition to being shifted to shorter wavelengths, is much more intense than that of the copperporphyrin a itself. The similarity of the absorption spectra of copper-porphyrin a and pyridine-haemochrome a, and their difference from the usual two-banded systems of mos...

When a temperature gradient is applied to a polymer solution, the polymer typically migrates to the colder regions of the fluid as a result of thermal diffusion ~Soret effect!. However, in recent thermodiffusion experiments on poly~ethylene-oxide! ~PEO! in a mixed ethanol/water solvent it is observed that for some solvent compositions the polymer migrates to the cold side, while for other compo...