Group order

In a dissociative process the reaction rate is expected to decrease as the strength of the metal to leaving ligand bond increases. This trend is generally observed in Co(III) ammine complexes. As can be seen in Table 2, a partial leaving group order is... 

Now, consider leaving group orders in general. The order of inertness at Pt(II) (which corresponds to the theoretically comprehensible trans effect series) is largely opposite to the order of ligands in the well-known spectrochemical series. ... 

Figure4.11 Comparison of experimental dissociation energies of gold intermetallic compounds with those of copper and silver from mass spectroscopic measurements by Cingerich and coworkers [18, 159, 173, 176] arranged in group order according to the periodic table.

Note the very important MISSING option in the PROC REPORT. This ensures that all of your data actually appear in the printed output. Without the MISSING option, PROC REPORT drops any observation with a missing GROUP, ORDER, or ACROSS variable. The NOWINDOWS option is used because this program is designed to run in batch mode and we do not want to run PROC REPORT interactively. 

The authors point out that all 1,3-dicarbonyl compounds exist in the solid as the enol forms, many of which are in the internally hydrogen-bonded syn configuration. All known structures of the latter materials appear to belong to one of two classes those in which the formal C-0(H) and 0=0 bonds are significantly different in length, and those in which they are not. The authors term the first group ordered and the second disordered, referring to the possible populations of the two states 59. 

At this point, it is important to mention that, in spite of the great variety of active centers (molecules, ions in solids, color centers, etc.), it can be demonstrated that only 32 point symmetry groups exist in nature. These 32 point symmetry groups (denoted by the so-called Schoenflies symbols) are listed in Table 7.1. The group order and... 

Symbol Group order Number of classes Crystalline system... 

Domain Group Order Genus Species Abbreviation... 

Mode of Cyclization" Resinb (Final Deprotection) Peptide9 Protecting Groups (Order of Orthogonality)11 Ref... 

It will be noted that the classes have orders 1, 2, and 3, which are all factors of the group order, 6. It can be proved by a method similar to that used in connection with the orders of subgroups, that the following theorem is true ... 

We can then determine the number and dimensions of the irreducible representations by using the familiar rules that there are as many irreducible representations as there are classes and that the sum of the squares of the dimensions of the irreducible representations must equal the group order. 

The replacement of X by pyridine in the complex PtX(dien)+ to give Pt(dien)py2+ (equation 549) has been studied under controlled conditions with a range of leaving groups X. These data are shown in Table is.1 87-1988 From these data the leaving group order is NOj > H20 > Cl- > Br > I- > N3 > SCN- > NO2 > CN-. Reactions such as these must be carried out under thermal conditions for accurate comparison since photoaquation can occur, albeit with a rather low quantum yield.1989 The volumes of activation of these reactions (equation 550) are all negative. An associative mechanism is proposed for the nucleophilic dependent path, but for the nucleophile independent pathway both associative and dissociative mechanisms need to be considered.1990... 

In the rest of this section we report results on some of the more recently used catalysts for the ROMP of NBE, taken in Group order. 

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