I use the following HELM string:
PEPTIDE1{A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.C.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E}|PEPTIDE2{G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.C.S.S.S.S.S.S.S.S.S.P.P.P.P.P.P.P.P.P.K.K.K.K.K.K.K.K.K.K.K.K.K}|CHEM1{[PEG2]}|CHEM2{[SMCC]}$PEPTIDE1,CHEM1,C:R3-1:R1|PEPTIDE2,CHEM2,C:R3-1:R1$G1(PEPTIDE1+CHEM1:2.5)|G2(PEPTIDE2+CHEM2:1.5)$$
and see the following properties which look like the mol wts and formulae of the CHEM monomers only.
If I expand the group I see a larger mol wt and formula.
Expanding or collapsing groups should not affect the mol wt and formula.
I use the following HELM string:![image](https://user-images.githubusercontent.com/3986896/39518200-23916054-4dfa-11e8-9a33-e8907b7fec3d.png)
PEPTIDE1{A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.A.C.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.D.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E.E}|PEPTIDE2{G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.G.C.S.S.S.S.S.S.S.S.S.P.P.P.P.P.P.P.P.P.K.K.K.K.K.K.K.K.K.K.K.K.K}|CHEM1{[PEG2]}|CHEM2{[SMCC]}$PEPTIDE1,CHEM1,C:R3-1:R1|PEPTIDE2,CHEM2,C:R3-1:R1$G1(PEPTIDE1+CHEM1:2.5)|G2(PEPTIDE2+CHEM2:1.5)$$
and see the following properties which look like the mol wts and formulae of the CHEM monomers only.![image](https://user-images.githubusercontent.com/3986896/39518114-d1147dac-4df9-11e8-9896-f35a3220e551.png)
If I expand the group I see a larger mol wt and formula.![image](https://user-images.githubusercontent.com/3986896/39518236-3e1930e6-4dfa-11e8-86b5-ddbd008259a0.png)
Expanding or collapsing groups should not affect the mol wt and formula.