I have a solid compound which can exist in both amorphous and crystalline forms. The properties we are intersted in is diplayed to a much higher degree in the crystalline form.

Info about the compound:

a) The compound is obtained as a solid after reversed phase column chromatography/liophilization and is amorphus

b) The compound is only somewhat stable at ambient temperature (~10% degradation after 2 months @ rt), but the stability is OK if it is kept in the dark @ 0 oC.

c) It is almost impossible to achieve crystallization from solvent systems/vapor diffusion/slow evaporation and any other regular crystallization methods - in these cases the compound spontaniously aggregates at some oversaturation level forming amorhous material

d) You cant heat the sample excessively because degradation occurs

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So an amorhous solid sample I had was left in the freezer for 2 years and crystalline compound formed. After resynthesizing the compound i would like to avoid waiting few years for it to achieve the crystalline form (I am not trying to achieve big crystals, nanocrystals would do here)

What can I do to accelerate the transfer from amorphous solid to crystalline solid?

One method I know does this is if You have a amorphous material for which crystalline form is favoured it is possible to stirr the amorphous material in a solvent in which it practically does not dissolve or dissolves very poorly, stirring for several days it is possible to achieve crystalline form of the compound. Note that in these cases the appearance of the material after filtration would hardly change, the main things that change are the properties of the material. I do know that a crystalline form is achieved because the sample before stirring shows no peaks in XRD analysis and after it does, this is aside from the property change which are easily observable.

I am looking for similar methods that could acheive cristallinity

Any ideas would be very welcome,

Thanks in advance,

Kaspars