Let's say we have pure, neutral water. From what I understand, this water will have H2O molecules, some hydronium and hydroxide ions (from the autoionization of water), and nothing else.

Now we put some DMT freebase in it.

According to the FB calculator, 34% DMT is in freebase form at pH 7. So 66% of the DMT should convert to salt form.

What salt will that be?

From what I understand the DMT salt will be a combination of DMT H+ and OH-. Would it be correct to call it DMT waterate? Because it was created by reacting DMT with water acid.

dimethyltryptammonium hydroxide, but technically only a tiny fraction would be dissolved and ionized, since DMT is not fully soluble in water

Pure H2O is actually relatively acidic and not the same as neutral water. I've measured the pH of distilled and 18.2 MOhm water (Millipore) and both have pH = ~ 5.5.

In the filtering process the water isn't equilibrated with atmospheric CO2. As it equilibrates later, water will react with the atmospheric carbon dioxide and produce H+ and HCO3- ions by way of a H2CO3 buffering system.

I agree with Mindillision's answer.

If you are into chem equations, then one possible representation of what you describe would be:

DMT-N + H2O <-> DMT-NH (+) and OH(-).

You could even claim that if you throw freebase DMT in plain water the pH will increase (more [OH-] species] and you wouldn't be wrong. Traditionally alkaloids were called as such because they behave in a way similar to alkalis (i.e. stuff that raise the pH of water).


Also,

Indeed, and pH will keep dropping the older the pure deionised water is - I have seen distilled deaionised water with a pH of 4!

Whaa,no way! Wow, I didn't know that, that's nuts