Ferrocene polymorphic forms

Figure 8.69 Space-filling representation of the three polymorphic forms of ferrocene (a) triclinic, (b) monoclinic, and (c) orthorhombic. (Reprinted with permission from [3] 1998 American Chemical Society) (d) Phase behaviour of ferrocene.

The possibility of different chemical behaviour of polymorphic modifications has been explored before only in the case of indomethacine amorphous and crystal forms reacted with ammonia by StoweU, Griesser, Bym et al. [62]. We have investigated two rather different systems, namely the polymorphic forms of barbituric acid [63] and of ferrocene dicarboxylic acids [64], which have been reacted with... 

A textbook example of conformational polymorphism is provided by ferrocene [44], for which one room temperature disordered and two low-temperature ordered crystalline forms are known. At the crystal level they differ in the relative orientation of the cyclopentadienyl rings and in small rotations of the molecules,... 

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