Structures of a dimorphic pentacoordinate silicon complex
The existence of polymorphs is of importance for many applications that depend on the solid state properties of a compound. TBPY-5-34-(Butane-1,4-diyl)(2-{[1-(2-oxidophenyl)ethylidene-
κO]amino-
κN}ethanolato-
κO)silicon, C
14H
19NO
2Si, crystallizes in two modifications. The monoclinic form, (IIm), was obtained by crystallization over a period of 2 days at room temperature; the orthorhombic form, (IIo), crystallized overnight at 248 K. According to thermal analysis it was concluded that (IIm) is the thermodynamically stable modification and (IIo) is a kinetically formed modification.
U. Böhme and I.C. Foehn