各位老师好，我先对ZnO单胞进行几何优化，再进行超胞P（3x1），切（100）面，thickness为3，固定两层原子，表面四层原子弛豫，截断能为340eV，k点2x4x1，对这个模型进行几何优化和计算能量，之后将NO2分子放在相同格子里进行几何优化和计算能量，再将优化后的NO2分子放在ZnO表面，对吸附模型进行几何优化，图1是原始模型。
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图2是使用的参数。
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第一次对该模型进行几何优化，程序运行11个小时，未能结束，因为还要使用电脑，我主动停止，收敛趋势图震荡严重。
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第二次对相同模型使用相同参数进行几何优化，运行约8.8小时得到结果，效率为100%。收敛趋势图为
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两次几何优化时.castep文件中均有三个warning存在:
1.BFGS: WARNING - trial step suggests complex energy landscape
in which simple line minimization will fail.
- This is usually an indication that the forces/streses
are not accurate enough. Consider making the following changes:
- Proceeding with a bisection search to find root instead.
2.BFGS: WARNING - looks like bisection search has failed?
BFGS: - reverting to earlier configuration and reseting inverse Hessian
3. BFGS: WARNING - Repeated consecutive reset of inverse Hessian
BFGS: without satisfying convergence criteria which
BFGS: looks like BFGS has run out of search directions.
BFGS: WARNING - Lets try allowing some uphill steps and see if
BFGS: we can get around this barrier.
BFGS: - It is possible that the system may now converge to
BFGS: a stationary point OTHER than the desired minimum.
BFGS: Hint - this may be an indication that either:
BFGS: a) you are using a poor guess at geom_frequency_est
BFGS: and/or geom_modulus_est, or
BFGS: b) you are using unrealistic convergence criteria.
BFGS: Suggest therefore that you consider changing them!