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标题: 求助：振动分辨的电子光谱计算出错 [打印本页]

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作者
Author: liaorongbao    时间: 2019-8-11 09:24
标题: 求助：振动分辨的电子光谱计算出错


Sob老师的博文http://sobereva.com/223
第一步：进行激发态计算如下
%rwf=SSexc.rwf
%nosave
%mem=30GB
%nprocshared=30
%chk=SSexc.chk
# maxdisk=500GB
#P wB97XD/6-31+G* TD opt int=ultrafine freq=saveNM  scrf=(solvent=acetonitrile)

it is already opted at wB97XD/6-31+G* scrf=(solvent=acetonitrile)

0 1
C                 -2.27482700   -0.67684600    0.13841000
C                 -3.37666400   -1.59428000   -0.14148200
O                 -3.28443300   -2.60572800   -0.82584500
O                 -4.54114700   -1.22585300    0.43084400
N                 -2.75174000    1.28735400    1.74718600
C                 -2.53455900    0.41319300    1.00708300
C                 -0.99077400   -1.03422800   -0.30606700
H                 -0.94839000   -2.06160800   -0.65625000
C                  0.21341600   -0.30230200   -0.27605500
C                  1.48777100   -1.01108100   -0.15095100
C                  2.64770800   -0.27603200    0.25484700
C                  2.57907100    1.12093600    0.43987100
H                  3.46787500    1.65683200    0.76410800
C                  1.42349200    1.84596100    0.10329000
C                  0.25068800    1.15188900   -0.33580600
C                  1.62037100   -2.39257000   -0.34678900
H                  0.77380300   -2.99082200   -0.66271900
C                  2.84169700   -3.04258500   -0.16119900
H                  2.90575900   -4.11281100   -0.32936000
C                  3.96852200   -2.32658700    0.24640500
H                  4.91540900   -2.83378100    0.40025200
C                  3.86831300   -0.95902000    0.45594700
H                  4.73791600   -0.39144500    0.77580500
C                  1.42741600    3.26019000    0.11079100
H                  2.30077300    3.78010100    0.49487400
C                  0.35144000    3.97950600   -0.39128600
H                  0.37747600    5.06439200   -0.39343500
C                 -0.74817700    3.29992600   -0.91885600
H                 -1.57640800    3.85214300   -1.35083900
C                 -0.79329700    1.90438600   -0.88937600
H                 -1.64525200    1.39991000   -1.33231800
H                 -5.21177300   -1.88447100    0.18691800

第二步：进行基态计算如下
%rwf=SSUVgr.rwf
%nosave
%mem=30GB
%nprocshared=30
%chk=SSUVgr.chk
# maxdisk=500GB
#P wB97XD/6-31+G* OPT freq=FC scrf=(solvent=acetonitrile) nosymm

it is already opted at wB97XD/6-31G* scrf=(solvent=acetonitrile)

0 1
分子结构说明

SSexc.chk


第三步：打开基态计算后的结果，发现出错情况如下：
     ==================================================
                 Duschinsky Transformation
     ==================================================

     ==================================================
              Calculations of Band Intensities
     ==================================================

Energy of the 0-0 transition:  19884.5994 cm^(-1)


Notes about the overlap integrals description:
  - DeltaE is the relative energy of the transition (wrt 0-0)
  - TDMI^2 is the square of the transition dipole moment integral
  - Intensity is the line intensity

ERROR: The Franck-Condon factor corresponding to the overlap integral
        between both vibrational ground states is too small:
         |<0'|0">|^2 =  0.13404E-08
Error termination via Lnk1e in /soft/g09/l718.exe at Sun Aug 11 17:48:54 2019.
Job cpu time:       1 days  3 hours 31 minutes 50.3 seconds.
File lengths (MBytes):  RWF=   1187 Int=      0 D2E=      0 Chk=     16 Scr=      1
为什么出错？|<0'|0">|^2 =  0.13404E-08是不是意味着没有紫外吸收光谱？如果0-0跃迁不行的话可以接着给出其他跃迁呀

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作者
Author: sobereva    时间: 2019-8-11 10:08
这部分代码开发者的文档里的答案

This error indicates that it is very likely that the underlying theory used to generate the spectrum, the Franck-
Condon principle, is unsuitable for the case of interest. This is a typical issue when the equilibrium geometry of the
initial and final states are noticeably different. This can happen when one of the structures is planar in one electronic
state and not planar in the other electronic state.
Another indicator of this problem is the Duschinsky matrix (which can be displayed with the option “PRTMAT=1”
in the ReadFCHT section) that shows the projection of the normal modes of one state on those of the other state. In
this case, the Duschinsky matrix is rather diffuse, that is to say that many normal coordinates of the final state are
expressed by a combination of a rather large number of normal modes of the initial state.
If the calculations must be carried anyway, this error can be bypassed with the keyword ForcedFCCalc. However,
please note that the resulting spectrum will be likely unreliable and the corresponding calculations should be
considered as tests.

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作者
Author: liaorongbao    时间: 2019-8-11 11:28
社长真细心！这都发现了。俺用 ForcedFCCalc看看可行，反正就是走个形式

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作者
Author: comboy2008    时间: 2019-8-14 17:41
社长对于该博文的前面几句话，请教社长，该方法在使用G16时会有更好的方法吗?如何实现?

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作者
Author: liaorongbao    时间: 2019-8-14 21:08

comboy2008 发表于 2019-8-14 17:41
社长对于该博文的前面几句话，请教社长，该方法在使用G16时会有更好的方法吗?如何实现?

感觉没读懂你问的是什么问题，尽管很关注。不知社长能否读懂

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