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README.md

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 Molecular dynamics
 
-A molecular dynamics simulation code has been created for relativistic and electromagnetic fields in three dimensions, and is used such as nanoscale particle phenomena. Maxwell equations are solved, and relativistic particles are then advanced in time. But, it is noted that the Gauss's equation must be corrected as finite errors accumulate in the divergence term. This is true if a discrete coordinated scheme is utilized in any method.
+A molecular dynamics simulation code has been created for relativistic and electromagnetic fields in three dimensions, and is used such as nanoscale particle phenomena. Maxwell equations are solved, and the momentum equations of relativistic particles are then advanced in time. But, it is noted that the Gauss's equation must be corrected as finite errors accumulate in the divergence term. This is true if a discrete coordinate scheme in any method is utilized.
 
 All explicit simulation code must satisfy the Courant condition, that is, Dx(length)/Dt(time step) > c, the speed of light. 
 Four physical CGS units are used in this code: a_unit= 1.00d-08 cm, t_unit= 1.00d-15 sec, electron mass m_unit= 0.9110d-27 g and its charge e_unit= 4.8032d-10 esu. The mass of hydrogen, for example, is 1.6726d-24 g. One needs files in the simulation: 1) @cnt3-3p8Ca.f03: Molecular dynamics simulation code, 2) param_em3p8_Ca.h: Common parameters of this simulation, 3) Cntemp_config.STARTC: figure parameters, 4) p_config_ss.xyz_D150 and P135: 4) Pellet electrons, H, C and Au ions. The program is written in Fortran 2003 and MPI version 3 for parallelization.