How are molecular structures determined?

[danceofdays]

My understanding of organic chemistry is pretty basic, and this is something I've been wondering for a while. How does one go about determining the structure / structural formula of a molecule? For example, say a new species of plant is discovered, with psychoactive effects when ingested. Once the alkaloid(s) are extracted, how are their structures found? What happens when a previously unknown molecule is discovered? How was this done historically?

If someone could give me a quick run-through that would be awesome. Thanks in advance!

 

[danceofdays]

bump?

 

[killermunchies]

I'd also be interested in hearing the answer to this. Anyone?

 

[fryingsquirrel]

Perhaps one of the mods could move this to ADD, I'm sure someone there knows. I'm curious about this also.

 

[Swerlz]

http://en.wikipedia.org/wiki/Molecular_geometry