Custom adduct types

[Tomnl]

It would be great if we could provide a more extended list of adducts to use with the MetFrag Galaxy tool. Currently we support only a few adduct types

In the MetFrag documentation "Further parameters" section in mentions "PrecursorIonMode" should be set for different adducts i.e.

Further Parameters
PrecursorIonMode
The adduct type of the precursor is used to calculate fragment masses. Following adduct types can be set by their appropriate numerical value encoding the following types:

positive (IsPositiveIonMode = True)
1	-	[M+H]+
18	-	[M+NH4]+
23	-	[M+Na]+
39	-	[M+K]+
33	-	[M+CH3OH+H]+
42	-	[M+ACN+H]+
64	-	[M+ACN+Na]+
83	-	[M+2ACN+H]+

negative (IsPositiveIonMode = False)
-1	-	[M-H]-
35	-	[M+Cl]-
45	-	[M+HCOO]-
59	-	[M+CH3COO]-

no adduct (IsPositiveIonMode = True/False)
0	-	[M]+/-

So I am wondering if these adduct types are hardcoded? or would it be safe to presume we could add in any other adducts as long as "PrecursorIonMode" is set to the rounded value of the adduct (e.g. [M+Na] is 23) and the correct neutral mass has been calculated for "NeutralPrecursorMass".

Do you know anything more about this @korseby?

@RJMW