doc/html/ directory installed with BKChem,
and other documentation on the
BKChem wiki.
BKChem is a 2-D tool for drawing chemical structures.
These notes are from 2009 May. As of 2014 Oct 10, the latest releases (according to Wikipedia) are from 2009 Feb 23 (stable) and 2010 Aug 12 (preview), and the project Web site does not respond.
This is a very brief introduction to a few of the tools, based
on my very limited experience, just to get a new user started.
For more details see the user's manual in the
doc/html/ directory installed with BKChem,
and other documentation on the
BKChem wiki.
The mode-selection panel is shown at the right.
To draw a chemical structure, click on the
tool and then click in the drawing area. A line will appear.
Click on one end of the line and a connected line will appear. To
control the orientation when creating a new line, click and drag in
the desired direction. Click in the middle of a line to change it to a
double or triple line. There are also tools for adding standard templates,
user-defined templates, arrows, etc.
To add or edit a node label, click on the
tool and then click on the node.
The text-entry area will become active. Enter the desired
node label and hit the Enter key. Some text strings will be recognized
and interpreted as element names; for example,
‘h’ or ‘H’
will be interpreted as hydrogen. The labels for carbon atoms are not
displayed; there is an option to not display hydrogen labels but I
haven't got it to work. There are also tools for marking atoms
with electrons, orbitals, etc.
To add or edit text, click on the
tool and then click in the drawing area
where the text is to appear. The text-entry area will become active.
Enter the desired text and hit the Enter
key. Some special formatting
is possible, such as bold and italics. New lines can be indicated
using \n but this seems to cause problems with subsequent
editing and is not well supported for display outside BKChem.
To select objects for moving or deleting, click on the
tool. Select an object by clicking on
it. Select multiple objects by using shift-click or by clicking and dragging
to surround the objects with a selection rectangle. Move selected objects
by clicking and dragging. The menu
contains tools for aligning objects horizontally and vertically.
Delete selected objects by using the Delete
or Backspace keys.
The native file format is a form of SVG. Two somewhat different SVG formats are
also exported, and two flavours of PDF are exported. My experience
(very limited) is that the most successful method is to just use the
native SVG file for display in Firefox. BKChem uses \n
to specify new lines in text but the new lines are respected only
in one of the PDF formats, and that format had other problems with
my example.
The \n also seemed to cause problems when editing
text so it may be best to avoid it altogether.