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The ground and metal-to-ligand (MLCT) excited electronic states of the complexes O~(bpy),,(P~)~-?+ (bpy = 2,2'-bipyridine, P2 = C~~-( C~H~)~P C H~H P ( C~H~)~; n = 1-3) have been studied by resonance Raman spectroscopy, time-resolved resonance Raman spectroscopy, and emission spectroscopy. The time-resolved resonance Raman evidence confirms that the charge-transfer electron density is localized in the lowest x * orbital of one bpy ligand rather than delocalized over the P* orbitals of all of the available bpy ligands on the vibrational time scale. The amount of charge transferred from the metal to bpy T * in the MLCT state has been determined. Application of Badger's rule to the Raman data and Franck-Condon analysis of the emission data lead to two independent determinations of average bond length displacements in the MLCT state. The two approaches yield displacement values that agree within 0.00 1-0.003 8, for the three complexes studied, suggesting that it may be possible to determine excited-state structures in solution with a precision similar to that of a good X-ray crystal structure. Analysis of time-resolved resonance Raman and emission data for Ru(bpy)?+, Ru(bpy),(en)2+, andfac-Re(bpy)(CO),CI by these methods yields results in agreement with the osmium data. The results suggest a general prescription for the determination of the molecular and electronic structures of electronically excited states in solution.As photochemical systems in solution, the metal-to-ligand charge-transfer (MLCT) excited states of d6 transition-metal complexes are rapidly becoming a paradigm. Information has appeared detailing both the photochemical and photophysical properties of many such systems.'-8 However, to date, essentially no quantitative information has emerged concerning molecular structure in this class of excited state in fluid solution. In this report we describe a study of this kind on the emitting MLCT excited states for the series of complexes Os(bpy),,(P2)3-;+ (bpy = 2,2'-bipyridine, P, = cis-l,2-bis(diphenylphosphino)ethylene (cis-Ph2PCH=CHPPh2); n = 1-3), which appear to be largely triplet in character but which contain considerable single character via spin-orbit coupling. The bases for our studies include both emission bandshape analyses and time-resolved resonance Raman spectroscopy. The results obtained allow us to infer quantitative information concerning both electronic and molecular structures for the M L C T excited states.Previously, time-resolved resonance Raman studies9-' I have conclusively established that the realistic formulation of the 600-ns-lived MLCT state of Ru(bpy)32+ is Ru"'(bpy), (bpy--),+; Le., the MLCT electron density is localized on a single bpy ligand on the time scale of molecular vibrations. This possibility had been suggested previously1as2 and has since been supported by several lines of evidence from a number of l a b o r a t~r i e s .~~~~~~J~J 'The experimental approaches employed in this study extend the conclusions concerning localization in MLCT excited states to the Os comp...

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This paper is the second in a series that describes how Modern Asset Pricing (MAP) may be used for project evaluation in the upstream petroleum industry. It has two goals. First, it demonstrates how MAP can be applied to the general class of projects where the project manager does not have any future flexibility that must be analysed. Second, the usefulness of MAP in fiscal system analysis is illustrated by the evaluation of a series of oil-field development projects under a variety of fiscal regimes. In situations where different fiscal systems have the same effect on a discounted cash flow (DCF) basis, the value of afield to a developer may appear quite different when analysed using MAP. MAP takes into account the differing risk characteristics of the cash-flow streams of the developer and the government or resource owner, and provides us with an added dimension of information: comparisons of how different fiscal systems distribute risk among the parties involved in the project.

It is hypothesized that the spatial occurrence of petroleum reservoirs can be represented by a Poisson process and that the sizes of the individual reservoirs are lognormally distributed. The total petroleum reserves occurring in any unit of space of arbitrary size within a region can thus be represented as a sum of lognormal random variables where the number in the sum is determined by a Poisson process. These hypotheses are tested, and a sampling experiment is conducted to demonstrate the estimation procedure.