anchor.diff:  
     open(17,file ='dimerdata_FullExp_1.txt')
     open(19,file ='dimerdata_vx_flow_wall.txt')  
  -
  +  open(18,file ='local_conc.txt')
     colloids% species(1) = 1
     colloids% species(2) = 2
     colloids% vel = 0
  
positive.code:   sigma_C = PTread_d(config, 'sigma_C')
    sigma_N = PTread_d(config, 'sigma_N')
  
    epsilon(:,1) = PTread_dvec(config, 'epsilon_C', 2)
    epsilon(:,2) = PTread_dvec(config, 'epsilon_N', 2)
  
    sigma(:,1) = sigma_C
    sigma(:,2) = sigma_N
  
negative.code:      if (i .gt. 2000) then
          fixed = .false.
       end if
       if (modulo(i,100)==0) then
          call concentration_field
          write(18,*) conc_z, colloid_pos
       end if
    end do setup
  
    call thermo_data%append(hfile, temperature, e1+e2+e_wall, kin_e, e1+e2+e_wall+kin_e, add=.false., force=.true.)
  