electron flow arrows hide lone pairs in Marvin 5.11.3

User 62a37f4796

09-11-2012 15:33:28

I've just started converting from 5.4 to 5.11 and I'm finding that electron flow arrow drawing has actually gotten worse.


 


In 5.4 the lone pair/radical electron dots would sometimes overlap electron flow arrows, but at least they would be stacked/shown on top of the arrow.


 


In 5.11.3 the dots are now completely hidden by the arrow. Moreover, the positioning of the electron dots on the origin atom is good before drawing the electron flow arrow, but is markedly worse after drawing the electron flow arrow. See the attached images. My concern is that students will have difficulty understanding what is happening and may try to "correct" entries that are visually imperfect, then causing them to submit an incorrect solution.


 


I know I can drag the arrow around on my end when I'm writing these questions for students, but I don't think (undergraduate) students would, nor should.


 


Any chance of seeing an improvement in the rendering any time soon?

User 62a37f4796

09-11-2012 16:03:26

Following on to the previous post on electron flow problems: in 5.4 (and 5.2 before it) electron flow arrows originated at the atom when you did an atom-to-atom electron movement; in 5.11 I have 2 electron flow arrows (1 2-electron and 1 1-electron flow to account for 3 electrons transferred) all originating from a single electron (radical) dot (instead of from the atom). Worse yet, when I try to draw 3 1-electron flow arrows as is the more likely sequence, 2 of the 1-electron flow arrows overlap. (See the snapshots attached.)


Whereas teaching electron flow arrows in 5.2 was a challenge, I'm afraid 5.11 is making it near impossible to properly reflect theory in what is being shown on the canvas.

ChemAxon f052bdfe3c

10-11-2012 09:19:26

Thank you for reporting this bug. We can see the problem here. The developer team will discuss by when we can fix it and I will inform you.