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【答案】应助回帖
感谢参与，应助指数 +1
你这应该是优化计算不收敛，不知道我下不了你的out文件，被浏览器禁了，不过我猜测你的文件这个错误信息前面应该有类似：
Maximum Force 0.020301 0.000450 NO
RMS Force 0.007068 0.000300 NO
Maximum Displacement 0.078972 0.001800 NO
RMS Displacement 0.023716 0.001200 NO
这样的语句吧，
你的问题应该是 优化不收敛，原因有好几种可能：（给你贴一些建议）
Geometry optimizations usually fail to converge for one of a few reasons.
If your initial starting structure is not good, then you should ask if you can provide a better starting structure, for example, one optimized at a lower level of theory. However, if it looks as if the structure is converging to what you want, as seen in your visualizer of choice, then one should restart the optimization from the last step, for example by using geom=allcheck in the route line, and it generally is a good idea to also use opt=CalcFC in these situations if it is not too expensive (say HF or DFT).
If your starting force constants matrix (Hessian) is poor, use a better one. This typically manifests itself when they vary a lot between levels, or if there is a large geometry change during the optimization. One can carry out a series of linked jobs (--Link1--). If you have a previous job, then usually Opt=ReadFC works well, but occasionally Opt=CalcFC, or rarely Opt=CalcAll are needed. In these cases, the forces are often converged, but the steps are not, and the final output will look like
Item Value Threshold Converged?
Maximum Force 0.000401 0.000450 YES
RMS Force 0.000178 0.000300 YES
Maximum Displacement 0.010503 0.001800 NO
RMS Displacement 0.003163 0.001200 NO
Rarely, the coordinate system itself may be at fault. If z-matrix coordinates are being used, then in some cases, poor choices can be made, which result in angles, or three consecutive atoms of the four atoms used to define a torsion angle (dihedral angle) may be collinear (the angle is close to 0 or 180 degrees), which can give problems. In this case one can either formulate a better z-matrix or use the default redundant internal coordinates.
If these methods fail, another option would be to change the optimization method from the default to another type, such as opt=ef (if the number of variables is less than 50) or opt=gdiis (for floppy molecules).
我的建议是，你先不做优化，直接坐energy计算，如果不能收敛，那说明你的初始结构是有问题的。其他则可以参考上面贴出来的信息 |
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wittymadder
