Configuration index priority numbers

Square planar coordination systems (SP-Jt The configuration index is a single digit which b the priority number Tor the ligating atom irons to the ligating atom of priority number l.33... 

The structural formula of this new cytostatic (picoplatin) is shown below. In determining the stereo descriptor, the situation arises here that the highest ranking ligand occurs twice. In such cases the priority number of the ligand coordinated trans to it with the lowest priority (i.e. with the highest priority number) is used as the configuration index (principle of trans maximum difference). 

Priming convention. The configuration index is especially useful for bis(tridentate) complexes and for more complicated cases. Bis(tridentate) complexes exist in three di-astereoisomeric forms which serve to illustrate the utility of a priming convention. These isomers are represented below, along with their site symmetry symbols and configuration indexes. For Examples I, 2, and 3, the two ligands are identical and the ligating-atom priority numbers are indicated. 

Each donor atom must be assigned a priority number based on the rules developed by Cahn, Ingold and Prelog (the CIP rules).13 These priority numbers are then used to form the configuration index for the compound. The application of the CIP rules to coordination compounds is discussed in detail in Section IR-9.3.5 but, in general, donor atoms that have a higher atomic number have higher priority than those that have a lower atomic number. 

The presence of polydentate ligands may require the use of primes on some of the numbers in the configuration index. The primes are used to indicate either that donor atoms are not part of the same polydentate ligand as those that have unprimed priority numbers, or that the donor atoms belong to different parts of a polydentate ligand that are related by symmetry. A primed priority number means that that donor atom has lower priority than the same kind of donor atom without a prime on the priority number. More detail on the priming convention can be found in Section IR-9.3.5.3. 

The configuration index for a square planar system is placed after the polyhedral symbol (SP-4). It is the single digit which is the priority number for the ligating atom trans to the ligating atom of priority number 1, i.e. the priority number of the ligating atom trans to the most preferred ligating atom. 

The configuration index for T-shaped systems follows the polyhedral symbol and consists of a single digit, the priority number of the ligating atom on the stem of the T (as opposed to the crosspiece of the T). 

The configuration index for see-saw systems consists of two digits, the priority numbers of the two ligating atoms separated by the largest angle. The number of lower numerical value is cited first. 

The methods for differentiating between stereoisomers outlined earlier in this Chapter require the assignment of priorities for the ligand atoms attached to the central atom (i.e. the donor atoms). These priority numbers are then used in the configuration index, which describes the relative positions of the ligands, and in the assignment of the absolute configuration of the compound. 

Sari and Kubat (2012) describe a model that provides an index of intervention designed to save maximum life within shortest term and with limited economic resources in case of an earthquake. In the first phase of the model, the definition of the vulnerability and calculations of the number and locations of people in danger are provided. The second phase of the process is the evaluation of the blockage risks of the roads within a network because of the collapsed buildings. Afterwards, predictions of the major routes that people use frequently to reach the city main road network and major destinations in the urban configuration are estimated with space syntax theory. The outputs of the model are the road risk and the index of intervention . Each value provides information for total risk assessment and intervention priorities against the earthquake risk. The model is applied to a case study from Istanbul, Turkey. 

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