This chapter provides a discussion of how informatics tools can address one of the fundamental historical developments in crystal chemistry, that of structure maps. Such maps serve as a means to ...explore how specific parameters associated with crystal and electronic structure can serve as a way to rationalize groupings, or classifications, relating structure and chemistry. Historically, structure maps have evolved through a variety of heuristic approaches that define a priori how parameters may be important, and then classifications are discovered as one populates these maps with data. The resulting clustering of data serves as a heuristic tool to rationalize new discoveries and new structure–bonding relationships.
Magnetic ordering Hauck, J; Mika, K
Journal of magnetism and magnetic materials,
04/2000, Volume:
212, Issue:
3
Journal Article
Peer reviewed
The ordering of magnetic moments in about 60 compounds containing M=Cr, Mn, Fe, Co, Ni, Pd, rare earths or U is analyzed by the self-coordination numbers of nearest, second and third neighbor ...positions
T
1,
T
2,
T
3 and the ratio
r=
y/
x of the equivalent positions
x and remaining positions
y. The plot of
T
1,
T
2 values for primitive cubic or hexagonal, face-centered or body-centered cubic lattices shows similar structures as in ordered alloys with small
T
2 values for attractive interactions and large
T
2 values at repulsive interactions. The intermediate interactions with
T
1,
T
2 values at the border of the structure map can be described by structure families with a combination of structural units.
Structure maps are presented as an efficient means of indicating structure-reactivity relationships in metabolic pathway databases. The relative occurrence of N-demethylation and N-oxidation of ...N-methyl tertiary amines was examined using the structure map methodology. A new family of reaction site representations, the n-level representations, was developed to describe the N-methyl reaction sites of the compounds in the data set. It was possible to differentiate N-demethylation and N-oxidation reaction sites using a structure map constructed from a 3-level representation of the reaction sites.