Probability interaction diagram

The question of the identity of the reactive excited state was left open, although n-n excited state was considered to be more probable.140 The interaction diagram, Fig. 7, shows that a n-n state would have an additional stabilizing interaction Ri(tt) ->-R2(7r) with orbital coefficients in phase for an all-suprafacial concerted reaction. The dominant reaction would theoretically depend upon the relative placements of the several levels, and since no experimental information for maleic and fumarate esters is presently available, a clear choice cannot be made. It is interesting that the reactive excited state could be inferred if both stereochemistry and a good molecular diagram were available. 

Structures. The methyl radical is planar and has D symmetry. Probably all other carbon-centerd free radicals with alkyl or heteroatom substituents are best described as shallow pyramids, driven by the necessity to stabilize the SOMO by hybridization or to align the SOMO for more efficient pi-type overlap with adjacent bonds. The planarity of the methyl radical has been attributed to steric repulsion between the H atoms [138]. The C center may be treated as planar for the purpose of constructing orbital interaction diagrams. 

An interaction diagram, as given in Section II, can be convenient to study the various interactions in reactive extrusion. A numerical model for closely intermeshing twin screw extruders, based on this diagram gives good results, except for the influence of the rotational speed on the final conversion, which is probably due to a retardation of the onset of the reaction connected to heat transfer problems. 

These diagrams focus on the temporal or time relationships of operations and they can be used to solve resource allocation problems, to determine whether there is any potential for time stress, and to consider alternative work methods in the execution of a procedure. An example drawn from traditional industrial engineering methods is shown in Figure 4.7. The chart is used to analyze the interaction between people and equipment. As indicated in the summary portion of this chart, there is a high proportion of idle time which would probably indicate the use of alternative procedures in the execution of this task. The chart enables the analyst to see the relationships among the activities of the different components in planning such alternatives. 

---