User guide

To draw, click in the document window with either the cyclopentadiene or benzene drawing tool.
To shift the orientation so the first bond drawn is a single bond, do one of the following:
Shift+drag from the beginning of the first single bond to the end of the single bond.
Shift+click in a document window to draw the bond with a Fixed Length.
Chains
You can draw hydrocarbon chains using either Acyclic Chain tool or Snaking Chain tool. Use Acyclic chain tool to
draw straight hydrocarbon chains.
1. Select the Acyclic Chain tool.
2. Click and drag in the document window in the direction you want the chain to grow. The number at the end of the
chain indicates how many atoms you have drawn.
Changing chain direction
To change the direction as you draw, use the Snaking chain tool, or press the CTRL key with Acyclic tool selected,
while drawing in the direction you want.
Note: Release the mouse button before you release the CTRL key.
Fixed length
Applying fixed lengths and fixed angles enables you to create structures with consistent bond lengths and angles. The
fixed length dimension is set in the Drawing Settings dialog box. The fixed angle dimension increments angles by 15
degrees.
Fixed length is used to constrain the length of the bonds drawn to the length you specify when the Fixed Lengths com-
mand in the Object menu is selected (a check mark is next to it). This also adjusts the preferred bond length for struc-
tures modified by the Clean Up Structure command.
When Fixed Lengths is on, the pointer on the acyclic chain can be dragged to make any angle relative to the X-axis. At
a constant chain length, the positions of the first bond and all subsequent odd-numbered atoms depend on the direc-
tion you drag. Before releasing the mouse button, this position can be changed by dragging in the opposite direction.
If Fixed Lengths is off, hold down the CTRL+ALT keys to reverse chain direction. Fixed Angles must be on to reverse
direction.
Fixed angle
When Fixed Angles is on, the angle the acyclic chain makes relative to the X-axis is constrained to 15-degree incre-
ments.
Adding chains to structures
To add an acyclic chain to an existing structure, click an atom in the structure. Click and drag in the direction you want
to draw the chain.
Specifying chain length
To specify the exact length of a chain before you draw it:
ChemBioDraw 13.0
Chapter 3: Basic drawings 29 of 401