style
Controls which 
style is applied by default when creating a new bond:
cylinders in 
solid mode, simple lines in 
wired mode.
Example: <bond style="wired"/> (default)
(defined in GAMGI_MESA_BOND_DRAW)
Allowed values: wired, solid (optional)
size
In 
solid mode, controls the size of the bond cylinders 
applied by default. Combining bond 
size with atom 
variancy and 
size, it is possible to obtain 
a wide range of styles to represent atomic structures.
The default is to represent atoms slightly larger than bonds:
<atom variancy="0.0" size="0.8"/><bond size="0.5"/>
An elegant style is to represent bonds with the same size as atoms:
<atom variancy="0.0" size="0.5"/><bond size="0.5"/>
To guarantee that bond cylinders are closed by atom spheres,
bond 
size should not be larger than atom 
size.
  
Example: <bond size="0.5"/> (default)
(defined in GAMGI_CHEM_BOND_SIZE)
Allowed values: positive real (optional)
color
Controls whether bonds have their own independent color, 
by default, or inherit the colors of the parent atoms.
Example: <bond color="no"/> (default)
Allowed values: yes, no (optional)
red, green, blue
Set the bond color used by default, when bonds 
are rendered with their own independent color.
Example: <bond red="0.0" green="0.8" blue="0.0"/> (default)
(defined in GAMGI_MESA_BOND_R, GAMGI_MESA_BOND_G, GAMGI_MESA_BOND_B)
Allowed values: 0.0 - 1.0 (optional, coupled)