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The title compound, tetrachlorido-1κ Cl;2κ3 Cl-(2,2,7,7,12,12,17,17-octamethyl-21,22,23,24-tetraazapentacyclo[16.2.1.13,6.18,11.113,16]tetracosane-1κ4 N, N′, N′′, N′′′)-μ2-oxido-diiron(III), [Fe2Cl4O(C28H52N4)], undergoes a slow phase transformation at ca 173 K from monoclinic space group P21/ n, denoted form (I), to the maximal non-isomorphic subgroup, triclinic space group P, denoted form (II), which is accompanied by nonmerohedral twinning [twin fractions of 0.693 (4) and 0.307 (4)]. The transformation was found to be reversible, as on raising the temperature the crystal reverted to monoclinic form (I). In the asymmetric unit of form (I), Z′ = 1, while in form (II), Z′ = 2, with a very small reduction ( ca 1.8%) in the unit-cell volume. The two independent molecules ( A and B) in form (II) are related by a pseudo-twofold screw axis along the b axis. The molecular overlay of molecule A on molecule B has an r.m.s. deviation of 0.353 Å, with the largest distance between two equivalent atoms being 1.202 Å. The reaction of calix[4]pyrrolidine, the fully reduced form of meso-octamethylporphyrinogen, with FeCl3 gave a red-brown solid that was recrystallized from ethanol in air, resulting in the formation of the title compound. In both forms, (I) and (II), the FeIII atoms are coordinated to the macrocyclic ligand and have distorted octahedral FeN4OCl coordination spheres. These FeIII atoms lie out of the mean plane of the four N atoms, displaced towards the O atom of the [OFeCl3] unit by 0.2265 (5) Å in form (I), and by 0.2210 (14) and 0.2089 (14) Å, respectively, in the two independent molecules ( A and B) of form (II). The geometry of the [OFeCl3] units are similar, with each FeIII atom having a tetrahedral coordination sphere. The NH H atoms are directed below the planes of the macrocycles and are hydrogen bonded to the coordinated Cl− ions. There are also intramolecular C-H...Cl hydrogen bonds present in both (I) and (II). In form (I), there are no significant intermolecular interactions present. In form (II), the individual molecules are arranged in alternate layers parallel to the ac plane. The B molecules are linked by a C-H...Cl hydrogen bond, forming chains along [100]. [ABSTRACT FROM AUTHOR]

A central claim of new institutional theory is that organizations in a field come to exhibit shared characteristics over time. Recent literature emphasizes variation across field members, but has yet to concur on why differences occur. This study tests institutional explanations for the uneven implementation of one organizational practice-outcome measurement, an evaluative technique used to assess the impact of an organization's programs. We analyze data from a new survey investigating the practices of nonprofit organizations (N = 379) and argue for the inclusion of the concept of organizational capacity to account for the uneven implementation of outcome measurement. As predicted by new institutional theory, organizations are more likely to adopt outcome measurement if key actors promulgate its use. However, the implementation of outcome measurement is best explained by the addition of the concept of organizational capacity alongside variables drawn from new institutionalism. Nonprofits with adequate organizational capacity, operationalized-following Weber's concept of bureaucracy-as the presence of written rules and members with specialized knowledge, are better able to respond to isomorphic pressures to implement a new organizational practice. Our findings expand scholarship that examines the intersection of institutional dynamics and organizational traits in accounting for patterns of implementation of practices across an organizational field. [ABSTRACT FROM AUTHOR]

In an earlier study on the audit services market, I showed that an individual client firm's likelihood of imitation in auditor selection systematically varied along with its relative position among competing peers within the industry. This paper extends that finding to the aggregate industry level by shifting the analytical focus from within-industry to between-industry variation. The data on 2254 auditor–client pairs across 45 manufacturing industries in the United States are examined to specify the social structural conditions under which the firms are more, or less, likely to produce the outcome of isomorphism. In general, the more hierarchically stratified an industry, the more likely it is to have a highly homogeneous practice among the firms within it. Inequality leads to and exacts behavioral homogeneity. There is, however, a threshold in the relationship between the aggregate homogeneity and the industry structure: When the disparity between the top and middle tiers is too large, the social reference process breaks down and the level of homogeneity declines. This industry-level finding complements the earlier firm-level finding and empirically substantiates the mechanism of mimetic isomorphism, further elaborating the theory. [ABSTRACT FROM AUTHOR]