应《网络安全法》要求，自2017年10月1日起，未进行实名认证将不得使用互联网跟帖服务。为保障您的帐号能够正常使用，请尽快对帐号进行手机号验证，感谢您的理解与支持！

24小时热门版块排行榜    

CyRhmU.jpeg
小木虫论坛-学术科研互动平台 » 计算模拟区 » 量子化学 » Gaussian » 【求助】使用TDDFT优化几何出错
51/1返回列表
查看: 1086  |  回复: 6
只看楼主@他人 存档 新回复提醒 (忽略) 收藏    在APP中查看
当前只显示满足指定条件的回帖，点击这里查看本话题的所有回帖

lixiaona158

木虫 (著名写手)

自由人

[交流] 【求助】使用TDDFT优化几何出错已有3人参与

输入：
%chk=4-TDDFT.chk
%mem=8GB
%nproc=8
%nproclinda=1
#p opt b3lyp/lanl2dz  td(nstates=3,direct,root=1,triplet)

4-TDDFT

0 1
Ir
O                  1              B1
O                  1              B2    2              A1
C                  2              B3    1              A2    3              D1

输出：
Root      1 not converged, maximum delta is    0.395124680447325
No map to state      2
You need to solve for more vectors in order to follow this state.
Error termination via Lnk1e in /public1/Gauss09.A02/g09/l914.exe at Thu Jul 29 04:51:36 2010.
Job cpu time:  0 days  7 hours 40 minutes 31.6 seconds.
File lengths (MBytes):  RWF=    672 Int=      0 D2E=      0 Chk=     64 Scr=      1

各位帮我看看怎么回事。我用同样的方法优化了好几个体系都没有错，只有这个出了错误，不知道怎么改。
回复此楼

» 猜你喜欢

» 本主题相关价值贴推荐，对您同样有帮助:
1楼2010-07-29 10:04:56
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

lihb734

铁杆木虫 (职业作家)

站在计算化学入门的门槛上
why not use UKS, i.e DeltaSCF method?
赞一下 回复此楼
前途光明，出路难觅！
3楼2010-07-29 10:19:10
 已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
查看全部 7 个回答

lihb734

铁杆木虫 (职业作家)

站在计算化学入门的门槛上
★ ★ ★ ★
小木虫(金币+0.5):给个红包，谢谢回帖交流
loovfnd(金币+3):整成英文，太难懂了。 2010-07-29 13:52:15
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.
赞一下(2人) 回复此楼
前途光明，出路难觅！
2楼2010-07-29 10:18:25
 已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

lixiaona158

木虫 (著名写手)

自由人
★ ★ ★
loovfnd(金币+3):后来修改后的命令贴一下吧！ 2010-07-29 13:55:23
感谢1楼详细的回答。
赞一下(1人) 回复此楼
4楼2010-07-29 10:36:46
 已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

lihb734

铁杆木虫 (职业作家)

站在计算化学入门的门槛上
★
小木虫(金币+0.5):给个红包，谢谢回帖交流
其实就是要调大nstates的参数值
赞一下(1人) 回复此楼
前途光明，出路难觅！
6楼2010-07-29 21:55:50
 已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
查看全部 7 个回答
普通表情 龙 兔 虎 猫 高级回复(可上传附件)
信息提示
关闭
请填处理意见
关闭