大家好，想做一个溶液体系，希望能够较清晰的看出添加剂加入时配位变化，所以体系中分子少一些，构建的也较小。构建1.9nm的立方体盒子，运行npt时出现错误。
Fatal error:t
One of the box vectors has become shorter than twice the cut-off length or box_yy-|box_zy| or box_zz has become smaller than the cut-off.
npt.mdp内容
title = NPT equilibration
define = -DPOSRES ; position restrain the protein
; Run parameters
integrator = md ; leap-frog integrator
nsteps = 6000000 ; 1 * 30000 = 30ps
dt = 0.001 ; 1 fs
; Output control
nstxout = 100 ; save coordinates every 0.2 ps
nstvout = 100 ; save velocities every 0.2 ps
nstenergy = 100 ; save energies every 0.2 ps
nstlog = 100 ; update log file every 0.2 ps
; Bond parameters
continuation = yes ; Restarting after NVT
constraint_algorithm = lincs ; holonomic constraints
constraints = all-bonds ; all bonds (even heavy atom-H bonds) constrained
lincs_iter = 1 ; accuracy of LINCS
lincs_order = 4 ; also related to accuracy
; Neighborsearching
ns_type = grid ; search neighboring grid cells
nstlist = 5 ; 10 fs
rlist = 0.9 ; short-range neighborlist cutoff (in nm)
rcoulomb = 0.9 ; short-range electrostatic cutoff (in nm)
rvdw = 0.9 ; short-range van der Waals cutoff (in nm)
; Electrostatics
coulombtype = PME ; Particle Mesh Ewald for long-range electrostatics
pme_order = 4 ; cubic interpolation
fourierspacing = 0.16 ; grid spacing for FFT
; Temperature coupling is on
tcoupl = V-rescale ; modified Berendsen thermostat
tc-grps = system ; two coupling groups - more accurate
tau_t = 0.1 ; time constant, in ps
ref_t = 300 ; reference temperature, one for each group, in K
; Pressure coupling is on
pcoupl = Parrinello-Rahman ; Pressure coupling on in NPT
pcoupltype = isotropic ; uniform scaling of box vectors
tau_p = 2.0 ; time constant, in ps
ref_p = 1.0 ; reference pressure, in bar
compressibility = 4.5e-5 ; isothermal compressibility of water, bar^-1
refcoord_scaling = com
; Periodic boundary conditions
pbc = xyz ; 3-D PBC
; Dispersion correction
DispCorr = EnerPres ; account for cut-off vdW scheme
; Velocity generation