Naphthas and generally aliphatics are perfect for freeze precipitation if one wants to get the dmt out of them. After this step they can be safely distilled (little if any dmt stays in the aliphatics after freeze-precip), so there's no need for fractional distillation.

DCM pulls on the other hand can be distilled as is due to the low boiling point of dcm.  This will leave you with a oily yellow residue comprising of dmt, dmt n-oxide, other alkaloids and rest oily/fatty crap. Mind you, SWIM has never bothered to straight distil dcm pulls though, because the residue'll be more difficult to clean.

Finally, nice to have you around here! We do need more of the science types!Which softwares do you use for your modellings? I also did some back in the past, it never won me though over the good old "wet" bench-work.