CCL:G: Low-progression Franck-Condon transitions



 Sent to CCL by: "Julien Bloino" [julien.bloino/./gmail.com]
 
A progression of 87% is good; this means that the most significant transitions have been included in the spectrum. The "final spectrum" reported by GaussView is the correct one. Gaussian prints in the output file a list of the "most important" transitions (by default, all transitions, which contribute to at least 1% of the total intensity). GaussView takes this list of transitions and broadens each peak (the "reported transitions"). This is a feature specific to GaussView. It can provide a visual aid in assessing the contribution of a given transition or a set of transitions to the overall band-shape or a specific band. The difference between the two spectra show the weight of low-intensity peaks to the overall intensity. This is indirectly a measure of the mode mixing, since a larger mode mixing tends to produce a higher number low-intensity transitions and so the two spectra will drift apart. Since the contributions from the vibronic transitions are additivie in one-photon absorption (the default, I assume what you did) or emission, then the spectrum obtained from the reported transitions should always be lower than the final spectrum (what you saw from my understanding), and equal if all significant transitions are reported.
 Best regards,
 Julien Bloino
 ------ Original Message ------
 
 From: "tianxiaohui|-|zju.edu.cn" <owner-chemistry- -ccl.net>
 
 To: "Bloino, Julien " <julien.bloino- -gmail.com>
 Sent: 2018-11-04 15:04:53
 Subject: CCL:G: Low-progression Franck-Condon transitions
 
 Sent to CCL by: tianxiaohui..zju.edu.cn
 dear Dr Julien,
 Thank you. Your explanations are very helpful.
 
I am confused by the TI results showed in GaussView. I can find two spectra there,one is directly broadened from the sticks (legend: Spectrum from reported transitions). But the second one (legend: The final spectrum), also the one printed in Gaussian output file, usually has higher 0-1 0-2 peaks than the other. I 'd like to know the difference and which should I use? By the way, the convergence of my TI result is 86.7%, is this value acceptable?
 Thanks a lot.
 Best regards.
 
 from Tian.
 
 
 -----原始邮件-----
 
发件人: "Julien Bloino julien.bloino~!~gmail.com" <owner-chemistry]=[ccl.net>
 发送时间: 2018-11-02 05:08:07 (星期五)
 收件人: "Tian, Xiaohui "
 <tianxiaohui]=[zju.edu.cn>
 抄送:
 主题: CCL:G: Low-progression Franck-Condon transitions
 Sent to CCL by: "Julien Bloino" [julien.bloino:_:gmail.com]
 Dear Dr. Krämer,
 As commented by Dr. Götze, the likely reason for the small progression
 is a significant shift of one or more modes.
 The keywords are for G16 and should be inserted in the `ReadFCHT`
 section (Freq=ReadFCHT).
 You can see the shift vector with
 `Print=Matrix=K`
 Depending on the symmetry and the structural changes, you may improve
 the convergence by increasing the maximum number of quanta for the
 overtones (MaxC1) and 2-modes combinations (MaxC2):
 `Prescreening=(MaxC1=20,MaxC2=13)` (those are the default values.)
 
This is rarely sufficient to fix the convergence issue and you may want
 to check the presence of low-frequency large amplitude modes (large
 shift of low-energy modes) and potentially exclude them as they are
 poorly treated with this model.
 You can do them with:
 `RedDim=Block`
 followed by the list of modes to exclude (the reference state is the
 lower state, so you will have to list the modes to exclude from the
 initial state, compatible with the definition of the shift vector K).
 Note that Gaussian will try to build a consistent set of modes (same
 number in each state) to exclude from the vibronic treatment. It has a
 
safety check to stop if too many modes are selected this way compared to
 the initial list. You can force it by changing the value of
 `RedDim=BlockTol`
 
The definition of the set of modes to exclude is based on the Duschinsky
 matrix, which can be printed with,
 `Print=Matrix=J` (we generally always print both J and K with
 `Print=Matrix=JK`)
 Be careful in the truncation as the model system obtained this way may
 not be representative of the full system anymore.
 To obtain a fully converged spectrum, you can use the time-dependent
 
formalism instead of the sum-over-states one (the default in this case)
 with the option
 `TimeDependent`
 I would recommend to use first TI to setup your protocol (trying the
 options described above) and once a sufficient convergence is reached,
 use TD to obtain the full band-shape. Indeed, the breakdown of the
 Franck-Condon approximation has a direct impact on a TI calculations
 (low and slow convergence) but is difficult to detect within the TD
 framework (the spectrum is always fully converged by definition).
 Regarding ForcePrtSpectrum, the option (and all "advanced" options) is
 
still there but I chose not to document it as it is a double-edged sword and could be misinterpreted. There are technically 2 separate checks but
 the one you mention will not be helpful in your case (at least in a
 first time).
 - the first test is on the overall convergence after 2-modes
 
combinations. If it is below 20% (which is the case here), Gaussian will
 stop. You can override this with
 `Advanced=ForceFCCalc`
 
- the second test is at the end of the calculations, before printing the spectrum. If the progression is below 50%, the spectrum is not printed.
 You can override this with
 `Advanced=ForcePrtSpectrum`
 Regarding the description of the potential energy surfaces, Gaussian
 supports AdiabaticHessian (AH, the default), AdiabaticShift (AS),
 VerticalHessian (VH, also noted VFC) and VerticalGradient (VG, aka LCM
 or IMDHO). From my understanding, a behavior similar to IMDHO-FA would
 be obtained in Gaussian with
 `VerticalHessian DataMod=Duschinsky=Identity`
 
Simplified models (like VG) should be used with care. While it is easier
 to reach convergence with them, they can also misrepresent the actual
 
system, leading to incorrect spectra. The validity of such approximation
 will depend on your system.
 I hope this will answer your questions regarding the progression and
 keywords.
 Best regards,
 Julien Bloino
 ------ Original Message ------
 
> From: "Tobias Kraemer Tobias.Kraemer!A!mu.ie" <owner-chemistry],[ccl.net>
 To: "Bloino, Julien " <julien.bloino],[gmail.com>
 Sent: 2018-10-30 03:36:55
 Subject: CCL:G: Low-progression Franck-Condon transitions
 >Dear Jan,
 >
 >
 >thanks for your reply. Sorry for being so unspecific in my post, I
 
>thought this was a more generic error that could be solved more easily.
 >You are right about the fact that the geometries of the ground and
 
>excited state of this ZnPc complex differ (not too a large extend, but >obviously enough). The ground state is planar with D4h symmetry, while
 >the structure of the (1st) excited state converges to a C2v-symmetric
 >geometry (consistent with literature J. Chem. Phys., 2015, 142,
 >094310). In fact the white paper by Barone "Vibrationally-excited
 >states in Gaussian09" mentions the distortion of the excited state
 >geometry away from a planar geometry in the ground state can cause
 >problems (and FC does not apply). However, since the aforementioned
 
>paper in J. Chem. Phys. presents a FC spectrum, I believe that it must >still be possible to generate the spectrum, and find a way around this
 >issue. I should also mention that by visual inspection the excited
 >state geometry is not hugely different from the ground state (but
 >obviously large enough to cause a problem). It seems in G09 one could
 >force the plot of a spectrum nonetheless, via FORCEPRTSPECTRUM. My
 >question was also regarding a range of other keywords that might be
 >useful here (MAXBANDS/MAXC1/MAXOVR..). So the question still stands,
 >since I think it must be possible to solve this issue.
 >
 >
 >Nonetheless, I might try one of your suggestions as well, thanks for
 >pointing me in this direction.
 >
 >
 >Best,
 >
 >
 >Tobias
 >
 >
 >
 >
 >Dr Tobias Krämer
 >
 >Lecturer in Inorganic Chemistry
 >
 >Department of Chemistry
 >
 >Maynooth University
 >
 >[Maynooth University PNG Trans]
 >
 >Maynooth University, Maynooth, Co. Kildare, Ireland.
 >
 >E: tobias.kraemer|-|mu.ie T: +353 (0)1 474 7517
 >
 >________________________________
 >>From: owner-chemistry+tobias.kraemer==mu.ie|-|ccl.net
 >><owner-chemistry+tobias.kraemer==mu.ie|-|ccl.net> on behalf of Jan
 >>Götze jgoetze[]zedat.fu-berlin.de <owner-chemistry|-|ccl.net>
 >Sent: Saturday, October 27, 2018 4:25:23 PM
 >To: Tobias Kraemer
 >Subject: CCL:G: Low-progression Franck-Condon transitions
 >
 >
 >Sent to CCL by: =?UTF-8?Q?Jan_G=c3=b6tze?=
 >[jgoetze##zedat.fu-berlin.de]
 >Dear Tobias,
 >
 >the data you provided only allow for limited analysis why your proble
 >occurs. In case you did not do any errors in preparation of your two
 
>excited states, it appears that the minima of ground and excited state
 >are very distant from each other (such as groups rotating, and/or
 >normal
 >modes differing strongly between ground and excited state). For a
 >large,
 >planar, aromatic system like pc this is rather unusual. As such,
 >without
 >further details on the molecular structure, any additional help can
 >only
 >be guesswork.
 >
 
>To obtain a preliminary spectrum quickly and often without problems, I
 >personally would suggest using a vertical TD approach, which might be
 >available in Gaussian16, or an IMDHO-FA as in ORCA. See for example
 >doi:10.1021/ct500830a
 >
 >Cheers,
 >Jan
 >
 >Am 26.10.2018 um 12:57 schrieb Tobias Kraemer tobias.kraemer[a]mu.ie:
 >>Sent to CCL by: "Tobias  Kraemer" [tobias.kraemer_._mu.ie]
 >>Hello everyone,
 >>
 
>>I am interested in calculating vibrationally-resolved spectra in G16.
 >>The
 >>molecule in question is a phthalocyanine (pc) complex. I've followed
 >>the
 >>protocol detailed in the whitepaper by Barone et al., however in the
 >>final step (generating the spectrum) an error occurs:
 >>
 >>
 >>       ==================================================
 >>                Calculations of Band Intensities
 >>       ==================================================
 >>
 >>   -- To: vibronic fundamental state --
 >>      Spectrum progression:    0.06%
 >>
 >>   -- To: single overtones --
 >>      Spectrum progression:    0.71%
 >>
 >>   -- To: combinations of  2 simultaneously excited modes --
 >>      Spectrum progression:    4.14%
 >>
 >>   ERROR: Low progression after class 2. Total convergence =  4.1%.
 >>          The vibronic spectrum will likely be unreliable. Stopping.
 >>
 
>>The whitepaper provides some possible causes, but I'd like to ask for
 >>some expert opinions here on CCL nonetheless. In the excited state
 
>>optimisation I have included 6 states, of which the gradients for the
 >>first one are to be followed [TD=(Read,NStates=6,Root=1)].
 >>There are a good number of keywords listed on the Gaussian16 webpage
 >>that
 >>relate to this type of calculation, and I'd appreciate some guidance
 >>on
 >>the above issue and possible ways around it.
 >>
 >>Thanks for your help, as always much appreciated.
 >>
 >>Kind regards,
 >>
 >>Tobias
 >
 >
 >-= This is automatically added to each message by the mailing script
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 >dir="ltr">
 ><p style="margin-top:0;margin-bottom:0">Dear Jan,</p>
 ><p style="margin-top:0;margin-bottom:0"><br>
 ></p>
 ><p style="margin-top:0;margin-bottom:0">thanks for your
 reply. Sorry
 >for being so unspecific in my post, I thought this was a more generic
 >error that could be solved more easily. You are right about the fact
 >that the geometries of the ground and excited&nbsp;state
 
>of this ZnPc complex&nbsp;differ (not too a large extend, but obviously
 >enough). The ground state is planar with D4h symmetry, while the
 >structure of the&nbsp;(1st)&nbsp;excited state converges to a
 >C2v-symmetric geometry (consistent with literature J. Chem. Phys.,
 >2015,
 >142, 094310). In fact the white paper by Barone
 >&quot;Vibrationally-excited states in Gaussian09&quot; mentions the
 
>distortion of the excited state geometry away from a planar geometry in
 >the ground state can cause problems (and FC does not apply). However,
 >since the
 >aforementioned paper in J. Chem. Phys. presents a FC spectrum, I
 >believe that it must still be possible to generate the spectrum, and
 >find a way around this issue. I should also mention that by visual
 >inspection&nbsp;the excited state geometry is not hugely different
 
>from the ground state (but obviously large enough to cause a problem). >It seems in G09 one could force the plot of a spectrum nonetheless, via
 >FORCEPRTSPECTRUM. My question was also regarding a range of other
 >keywords that might be useful here (MAXBANDS/MAXC1/MAXOVR..).
 >So the question still stands, since I think it must be possible to
 >solve this issue.</p>
 ><p style="margin-top:0;margin-bottom:0"><br>
 ></p>
 ><p
 style="margin-top:0;margin-bottom:0">Nonetheless,&nbsp;I might
 try
 >one of your suggestions as well, thanks for pointing me in this
 >direction.</p>
 ><p style="margin-top:0;margin-bottom:0"><br>
 ></p>
 ><p style="margin-top:0;margin-bottom:0">Best,</p>
 ><p style="margin-top:0;margin-bottom:0"><br>
 ></p>
 ><p style="margin-top:0;margin-bottom:0">Tobias</p>
 ><p style="margin-top:0;margin-bottom:0">&nbsp;
 &nbsp;</p>
 ><p style="margin-top:0;margin-bottom:0"><br>
 ></p>
 ><div id="Signature">
 
><div id="divtagdefaultwrapper" dir="ltr" style="font-size: 12pt; color:
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><p class="x_MsoNormal" style="margin:0cm 0cm 0.0001pt; font-size:12pt;
 >font-family:&quot;Times New Roman&quot;,serif;
 color:rgb(33,33,33)">
 ><span style="font-size:9pt;
 >font-family:Arial,sans-serif,serif,EmojiFont;
 >color:rgb(35,31,32)"><b>Dr Tobias
 Krämer</b></span></p>
 
><p class="x_MsoNormal" style="margin:0cm 0cm 0.0001pt; font-size:12pt;
 >font-family:&quot;Times New Roman&quot;,serif;
 color:rgb(33,33,33)">
 ><span style="color:rgb(35,31,32);
 >font-family:Arial,sans-serif,serif,EmojiFont;
 font-size:9pt">Lecturer
 >in Inorganic Chemistry</span><br>
 ></p>
 
><p class="x_MsoNormal" style="margin:0cm 0cm 0.0001pt; font-size:12pt;
 >font-family:&quot;Times New Roman&quot;,serif;
 color:rgb(33,33,33)">
 ><span style="color:rgb(35,31,32);
 
>font-family:Arial,sans-serif,serif,EmojiFont; font-size:9pt">Department
 >of Chemistry</span></p>
 
><p class="x_MsoNormal" style="margin:0cm 0cm 0.0001pt; font-size:12pt;
 >font-family:&quot;Times New Roman&quot;,serif;
 color:rgb(33,33,33)">
 ><span style="font-size:9pt;
 >font-family:Arial,sans-serif,serif,EmojiFont;
 >color:rgb(35,31,32)">Maynooth
 University&nbsp;</span></p>
 
><p class="x_MsoNormal" style="margin:0cm 0cm 0.0001pt; font-size:12pt;
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 color:rgb(33,33,33)">
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><p class="x_MsoNormal" style="margin:0cm 0cm 0.0001pt; font-size:12pt;
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 color:rgb(33,33,33)">
 ><span style="font-size:9pt;
 >font-family:Arial,sans-serif,serif,EmojiFont;
 >color:rgb(35,31,32)">Maynooth University, Maynooth, Co. Kildare,
 >Ireland.</span></p>
 
><p class="x_MsoNormal" style="margin:0cm 0cm 0.0001pt; font-size:12pt;
 >font-family:&quot;Times New Roman&quot;,serif;
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 ><b style="font-size:12pt"><span
 style="font-size:9pt;
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 style="font-size:9pt;
 >font-family:Arial,sans-serif,serif,EmojiFont;
 >color:rgb(35,31,32)">tobias.kraemer|-|mu.ie&nbsp;<b>T</b><b>:</b>&nbsp;&#43;353
 >(0)1 474 7517</span></p>
 ><p
 style="font-family:Calibri,Arial,Helvetica,sans-serif,&quot;Apple
 
>Color Emoji&quot;,&quot;Segoe UI Emoji&quot;,NotoColorEmoji,&quot;Segoe
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 ></div>
 ><hr style="display:inline-block;width:98%"
 tabindex="-1">
 ><div id="divRplyFwdMsg" dir="ltr"><font
 face="Calibri, sans-serif"
 >style="font-size:11pt"
 color="#000000"><b>From:</b>
 >owner-chemistry&#43;tobias.kraemer==mu.ie|-|ccl.net
 >&lt;owner-chemistry&#43;tobias.kraemer==mu.ie|-|ccl.net&gt; on
 behalf
 >of Jan Götze jgoetze[]zedat.fu-berlin.de
 >&lt;owner-chemistry|-|ccl.net&gt;<br>
 ><b>Sent:</b> Saturday, October 27, 2018 4:25:23 PM<br>
 ><b>To:</b> Tobias Kraemer<br>
 
><b>Subject:</b> CCL:G: Low-progression Franck-Condon transitions</font>
 ><div>&nbsp;</div>
 ></div>
 
><div class="BodyFragment"><font size="2"><span style="font-size:11pt;">
 ><div class="PlainText"><br>
 >Sent to CCL by: =?UTF-8?Q?Jan_G=c3=b6tze?=
 >[jgoetze##zedat.fu-berlin.de]<br>
 >Dear Tobias,<br>
 ><br>
 >the data you provided only allow for limited analysis why your proble
 ><br>
 >occurs. In case you did not do any errors in preparation of your two
 ><br>
 
>excited states, it appears that the minima of ground and excited state
 ><br>
 >are very distant from each other (such as groups rotating, and/or
 >normal <br>
 >modes differing strongly between ground and excited state). For a
 >large, <br>
 >planar, aromatic system like pc this is rather unusual. As such,
 >without <br>
 >further details on the molecular structure, any additional help can
 >only <br>
 >be guesswork.<br>
 ><br>
 
>To obtain a preliminary spectrum quickly and often without problems, I
 ><br>
 >personally would suggest using a vertical TD approach, which might be
 ><br>
 >available in Gaussian16, or an IMDHO-FA as in ORCA. See for example
 ><br>
 >doi:10.1021/ct500830a<br>
 ><br>
 >Cheers,<br>
 >Jan<br>
 ><br>
 >Am 26.10.2018 um 12:57 schrieb Tobias Kraemer
 >tobias.kraemer[a]mu.ie:<br>
 >&gt; Sent to CCL by: &quot;Tobias&nbsp; Kraemer&quot;
 >[tobias.kraemer_._mu.ie]<br>
 >&gt; Hello everyone,<br>
 >&gt;<br>
 >&gt; I am interested in calculating vibrationally-resolved spectra in
 >G16. The<br>
 >&gt; molecule in question is a phthalocyanine (pc) complex. I've
 >followed the<br>
 >&gt; protocol detailed in the whitepaper by Barone et al., however in
 >the<br>
 >&gt; final step (generating the spectrum) an error occurs:<br>
 >&gt;<br>
 >&gt;<br>
 >&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 >==================================================<br>
 >&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 >Calculations of Band Intensities<br>
 >&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 >==================================================<br>
 >&gt;<br>
 >&gt;&nbsp;&nbsp; -- To: vibronic fundamental state --<br>
 >&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Spectrum
 >progression:&nbsp;&nbsp;&nbsp; 0.06%<br>
 >&gt;<br>
 >&gt;&nbsp;&nbsp; -- To: single overtones --<br>
 >&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Spectrum
 >progression:&nbsp;&nbsp;&nbsp; 0.71%<br>
 >&gt;<br>
 
>&gt;&nbsp;&nbsp; -- To: combinations of&nbsp; 2 simultaneously excited
 >modes --<br>
 >&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Spectrum
 >progression:&nbsp;&nbsp;&nbsp; 4.14%<br>
 >&gt;<br>
 >&gt;&nbsp;&nbsp; ERROR: Low progression after class 2. Total
 >convergence =&nbsp; 4.1%.<br>
 
>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The vibronic
 >spectrum will likely be unreliable. Stopping.<br>
 >&gt;<br>
 
>&gt; The whitepaper provides some possible causes, but I'd like to ask
 >for<br>
 >&gt; some expert opinions here on CCL nonetheless. In the excited
 >state<br>
 
>&gt; optimisation I have included 6 states, of which the gradients for
 >the<br>
 >&gt; first one are to be followed
 [TD=(Read,NStates=6,Root=1)].<br>
 >&gt; There are a good number of keywords listed on the Gaussian16
 >webpage that<br>
 >&gt; relate to this type of calculation, and I'd appreciate some
 >guidance on<br>
 >&gt; the above issue and possible ways around it.<br>
 >&gt;<br>
 >&gt; Thanks for your help, as always much appreciated.<br>
 >&gt;<br>
 >&gt; Kind regards,<br>
 >&gt;<br>
 >&gt; Tobias<br>
 ><br>
 ><br>
 >-= This is automatically added to each message by the mailing script
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