Acta Phys. -Chim. Sin. ›› 1994, Vol. 10 ›› Issue (11): 998 -1003.doi: 10.3866/PKU.WHXB19941107

• ARTICLE • Previous Articles     Next Articles

Head Group Effect on Molecular Dynamics Simulation of Labgmuir Monolayers

Zhang Hong-Yu, Wei Yu   

  1. Chien-Shiung Wu Laboratory of Southeast University,Nanjing 210028
  • Received:1993-09-24 Revised:1994-03-23 Published:1994-11-15
  • Contact: Zhang Hong-Yu


The structure and thermodynamics of stearate Lamgmuir film were studied using Molecular Dynamics and the effect of head group model on the simulation was also studied. The monolayer experienced two phase transitions during compression. The molecular chains tilted to their neighbors with a collective behavior and the bigger the density of the film is, the less tilted the chains are. The disorder occuring in molecules is mainly caused by the torsion of the dihedrals at the two ends of the molecular chains. It can be seen from the comparison of different models that the distribution of molecules with charged heads is more disordered and the tilted angle is a little bit smaller than those of neutral heads, which shows the difference in head group and subphase could influence the results of simulation, and it is important to find more reasonable head group model to improve the simulation.

Key words: Molecular Dynamics, Phase transition, Langmuir films, Head group