紫外吸收和荧光发射光谱计算

flyskyzff

       各位大侠好，在下刚接触一个荧光化合物的光谱计算，先不考虑溶剂效应，在气相gas phase下，1）基态结构的优化频率计算，2）垂直激发能的TD-DFT计算，3）在第一步优化好的基态结构基础上进行第一单重激发态结构的优化.....       本人想计算荧光发射光谱，在第（3）步中gaussian结果运行出错，TD-DFT和CIS方法都试了，都出现l914错误，这是输入文件的执行路径：# TD=(Singlets,NStates=6,root=1) b3lyp/6-31g(d) opt 或者 # CIS(Singlets,root=1)/6-31g(d) opt ，电荷与自旋多重度和基态一样都设为0 1，请大师们指点下吸收和发射光谱计算注意的各处细节。

sobereva

不要问link几几几错误怎么办，应该将错误提示贴出来。导致一个link出错的原因数不胜数。你的关键词本身写得没错，错误原因得具体问题具体分析。

flyskyzff

sobereva 发表于 2014-11-20 11:29
不要问link几几几错误怎么办，应该将错误提示贴出来。导致一个link出错的原因数不胜数。你的关键词本身写得 ...

化合物结构

输出：New state      1 was old state      2
New state      2 was old state      1
Excitation Energies [eV] at current iteration:
Root      1 :    12.938967165563460
Root      2 :    21.251407413606670
Root      3 :    21.510835624117890
Iteration     2 Dimension    12 NMult    12
Cannot handle 2e integral symmetry, ISym2E=1.
CISAX:  IP=  1 NPass=   1 NMax=     6.
CISAX will form     6 AO SS matrices at one time.
NMat=     6 NSing=     6.
Cannot handle 2e integral symmetry, ISym2E=1.
CISAX:  IP=  1 NPass=   1 NMax=     6.
CISAX will form     6 AO SS matrices at one time.
NMat=     6 NSing=     6.
Root      1 not converged, maximum delta is    0.545140015300988
No map to state      2
You need to solve for more vectors in order to follow this state.
Error termination via Lnk1e in /home/program/Gaussian/g09/l914.exe at Fri Nov 14 05:32:46 2014.
Job cpu time:  1 days  7 hours 41 minutes 25.9 seconds.
File lengths (MBytes):  RWF=    316 Int=      0 D2E=      0 Chk=     20 Scr=      1

sobereva

设大NStates再试

小范范1989

flyskyzff 发表于 2014-11-20 13:08
化合物结构

输出：New state      1 was old state      2

加入direct可否？

flyskyzff

小范范1989 发表于 2014-11-21 09:56
加入direct可否？

还是不行，想找个做过的例子，最好是发表的论文上的例子，发来输入文件学习学习就好了

sobereva

You need to solve for more vectors in order to follow this state.
这种错误提示直接的原因就是因为nstates数不够大。设大后还不行就设得更大
direct和这个问题无关

sobereva

官方对于这类问题的回复

I have consulted this question with Gaussian Technique Support, and following are their answers. Please notice the last paragraph.
Also, you can try use the last structure to restart the optimization or add the direct options to TDDFT.

In the case of "No map to state **, you need to resolve more vectors" messages, this is usually an indication that one did not include enough excited states in the TD or CIS calculation. The "States=N" option to the "TD" or "CIS" keywords tells how many excited states to include in an excited state energy calculation. If this is not specified, the default value will be "States=3". The recommended value is to include a minimum of 2 or 3 more states than the state of interest. Thus, if you want to perform a geometry optimization for excited state 5, for example, I would recommend at least using "States=7" or "States=8". The geometry optimization will be done for one excited state M, selected with "Root=M", and one has to make sure that enough states are included in the CIS or TD expansion by having "States=N" where N is larger than M.

It is possible that, at some point during an optimization of an excited state, the order of the excited states changes and the CIS or TD expansion might need to include more states in order to be able to follow correctly the state of interest. This is essentially what that message about including more vectors mean, that is that at that point, the number of states that you originally specified with "States=N" was not enough in order to solve for the state of interest, so a larger number "N" will need to be used for "States=N".

Other times, the problem is that the ground state wavefunction becomes unstable, that is one of the states that was an excited at the initial geometry now becomes lower in energy than the state that was the ground state at the initial geometry. This kind of situation, unfortunately, cannot be modeled properly with single determinant expansions such as CIS or TD, and one would need to use CAS in order to be able to deal with the conical intersection or avoided crossing of states.

Another thing to note is that one should be much more careful with geometry optimizations on excited states than for the ground state. Typically the energy differences among excited states are smaller than between the ground state and the first excited state. Thus, one can afford to perform larger geometry optimization steps when optimizing the ground state than in the case of optimizing an excited state.

A "bad" geometry optimization step in the optimization of the ground state, may take you a bit off track but in following steps the optimization might find the way back and approach the converged structure. In the case of an optimization of an excited state, a "bad" geometry optimization step will also take you off track but, since other electronic states are close in energy, it is possible that at the new geometry the order of the excited states change and now the geometry optimization follows a different electronic state.

This is not only a problem because the optimization could be pursuing a different state than the one you were interested in, but also because, if several of these changes occur during a geometry optimization, it may even be hopeless to continue with the optimization because the gradient information and the estimated hessian could be useless (since not all the previous points in the geometry optimization where points from the same potential energy surface).

As a first measure to increase the reliability of the geometry optimization of excited states, I recommend to reduce the maximum allowed step size during geometry optimizations. Try "Opt=(MaxStep=10)" to set this value to 0.10 Bohr, or a smaller value if you still have problems. The default value is typically 0.30 Bohr. Reducing the maximum allowed step size will result in the geometry optimization taking more steps to reach convergence than with the default value. This will be true obviously for well-behaved geometry optimizations, but for problematic cases it will be the other way around, i.e. it will take fewer steps (and may even be impossible with the default step size) because it will be easier for the optimizer to follow a particular electronic state if the changes from step to step are not very drastic.

flyskyzff

sobereva 发表于 2014-11-23 11:55
官方对于这类问题的回复

I have consulted this question with Gaussian Technique Support, and follow ...

感谢sobereva老师

flyskyzff

sobereva 发表于 2014-11-23 11:55
官方对于这类问题的回复

I have consulted this question with Gaussian Technique Support, and follow ...

Gaussian计算完之后，接下来我需要作出吸收光谱和荧光光谱谱图，有哪些方法软件怎么提取数据作图分析呢？ 这是激发态优化得到的结果：
Excitation energies and oscillator strengths:
Excited State   1:      Singlet-A      3.2075 eV  386.54 nm  f=0.0014  <S**2>=0.000
      12 -> 13        -0.70615
This state for optimization and/or second-order correction.
Total Energy, E(TD-HF/TD-KS) =  -153.705918872   
Copying the excited state density for this state as the 1-particle RhoCI density.

Excited State   2:      Singlet-A      6.6681 eV  185.94 nm  f=0.0748  <S**2>=0.000
       9 -> 13        -0.17810
      10 -> 13         0.39499
      11 -> 13         0.54184

Excited State   3:      Singlet-A      6.9177 eV  179.23 nm  f=0.0267  <S**2>=0.000
      12 -> 14        -0.66951
      12 -> 15         0.19242
      12 -> 16         0.10063

如何作出类似如下这些谱图呢?:

sobereva

这些图没有什么特殊的，只不过是多个曲线同时作到一张图，用origin就可以轻易做到，然后稍微ps而已
获得曲线图的过程可参考
使用Multiwfn绘制红外、拉曼、UV-Vis、ECD和VCD光谱图
http://sobereva.com/224

flyskyzff

sobereva 发表于 2014-11-27 09:52
这些图没有什么特殊的，只不过是多个曲线同时作到一张图，用origin就可以轻易做到，然后稍微ps而已
获得曲 ...

sob老师你好，我想知道作这些图，我应该从高斯输出文件中提取哪些关键有用的数据。。。

sobereva

就是用高斯输出的激发能、振子强度。
通过这个才能得到曲线，在帖子里写得十分详细

flyskyzff

sobereva 发表于 2014-11-27 10:38
就是用高斯输出的激发能、振子强度。
通过这个才能得到曲线，在帖子里写得十分详细

sob老师多谢你的回复。Multiwfn有吸收光谱的例子，那荧光发射光谱图绘制和UV-Vis一样呢~

sobereva

计算荧光时，只不过把几何结构从计算吸收光谱时的基态的平衡结构改成激发态的平衡结构，其它操作完全一样