Dear All, I have some basic questions about ESPResSO that I couldn't figure out the answer.
I am writing some basic scritps for 3D colloids (beads) that interact via the repulsive part of
Yukawa potential (Debye-Huckel in ESPResSO). Righ now, I can calculate
the radial distribution function, the structure factor and the MSD.
a) First, I want to study structural and dynamical properties of these systems in 2D. What I did to simulate a two-dimensional was: # --- The simulation Box is periodic in both directions setmd periodic 1 1 0 # --- Simulation Box setmd box_l $bl $bl $bl & during the cycle to place the particles inside the simulation box: part $i pos $posx $posy $posz type 0 q $zeff fix 0 0 1 so, my question is: Is this the best way to model a 2Dim system in ESPResSO ? Should I do something similar for 1D?
b) Also, I am interested in binary mixtures of Yukawa colloids.
However, I don't know how to specify the interactions for mixtures in
ESPResSO. For potentials like Lennard-Jones you can specify the type of
the particles: inter type1 type2 lennard-jones... but... how I can do the same for the Debye-Huckel potential ? It is possible to specify different Bjerrum lengths for the species?
c) Finally, I am using the example provided in the user's guide to
calculate the average of the gr and Sq. But (sometimes) when I stored
many files configurations (to improve the statistics), I have some
problems when I tried to calculate the averages of the gr & Sq. The
result during the average is the next:
missing operand at address@hidden in _expression_ "0 + address@hidden" (parsing _expression_ "0 + ") invoked from within "expr $ai + $bi" (procedure "vecadd" line 3) invoked from within "vecadd $avg_rdf $rdflist" ("for" body line 34) invoked from within "for {set i 1 } { $i <= $nfiles } { incr i } { set filename Pos$i set f [open "$filename" "r" ] while { [blockfile $f read auto] != "eof" } {..." (file "Debye-H.tcl" line 463)