From: Luca Bellarosa (lbellarosa_at_ICIQ.ES)
Date: Wed Apr 09 2014 - 09:29:21 CDT

Hi everybody,

my name is Luca and I'm preparing the video of a dynamics (25 ps) using VMD. During this trajectory, some atoms change their coordination and I wanted to highlight this phenomenon by changing smoothly the colors of the atom. Unfortunately, I cannot manage to even change the color during a given femtosecond.

My goal is the following:
-) When the atom is 4-fold coordinated, the atom is yellow (RGB 1 1 0.36).
-) When the atom is 5-fold coordinated, the atom is orangish (RGB 0.9 0.5 0.18).
-) When the atom is 6-fold coordinated, the atom is red (RGB 0.8 0 0).

I wrote a tcl script with the following commands:

---------------------tcl script--------------------------------------------------------------------------------
# I read the coordination "c" from a file; "c" can be any real value between 4 and 6.

set ix [expr {1.00 - ($c-4)*0.10}]
set iy [expr {1.00 - ($c-4)*0.50}]
set iz [expr {0.36 - ($c-4)*0.18}]

color atom 262 { $ix $iy $iz } # I chose the atom 262, but it can be anything

---------------------tcl script--------------------------------------------------------------------------------

But it gives me the following message: "Unable to change color name". I think I know how I can do it for all the frames, but I need to solve this problem with just one frame.

Thank you in advance for any help you can give me,


 Luca Bellarosa
 Postdoc Researcher, Institut Català d’Investigació Química (ICIQ)
 Av. Països Catalans 16 – 43007 Tarragona
 Tel +34 977920229 (Ext. 307) – Fax +34 977920231

Dalla scuola di guerra della vita. Tutto ciò che non mi uccide, mi rafforza. (F.Nietzsche, "Il crepuscolo degli idoli")