I am performing a melting simulation for cdh23 over a range of 298K to 400K. I have initially simualated at specific temperature from 300K to 400K at an interval of 5K. there seems to be no change in the protein structure. To perform the before mentioned simulation i had used fix nvk to keep the kinetic energy constant to observe the various conformations and change in potential energy. Now i want a simulation such that it heats the system from 298K to 400K but there are way too many fluctuations and I want the temperature to increase linearly.
I am attaching the code below
units real
boundary p p p
atom_style bond
bond_style fene/sop
pair_style hybrid lj/cut/sop/native 200 lj/cut/sop/nn 200
special_bonds lj 0.0 1.0 1.0
read_data p47_new.data
neighbor 3.0 bin
neigh_modify delay 0 every 5 check yes
compute native all pair lj/cut/sop/native epair
compute nonnative all pair lj/cut/sop/nn epair
fix 1 all nve
velocity all create 298.0 123456 dist uniform
fix 2 all langevin 298 400 1.0 123456
dump 2 all atom 1000 cdh23.lammpstrj
timestep 01.0
thermo_style custom step pe ke temp ebond c_nonnative c_native
log log_375.lammps
thermo 10000
run 1000000