Progress in dynamical mean field-based electronic structure methods over the last years has provided us with precious tools allowing for a microscopic understanding of electronic mechanisms at work in correlated materials, including functional materials. In this talk, we will focus on layered transition metal sulphides studied for battery applications. Analysing the electronic structure, energetics and intercalation voltage, we find that Hund’s exchange coupling plays a crucial role for the electrochemistry of these compounds. We identify the battery charging process as a transition from a high-spin Mott insulator to a low-spin correlated metal. We argue that a deeper understanding of the microscopic mechanisms at work in such materials might contribute to paving the way to better battery materials in the future. More details: https://www.simonsfoundation.org/event/dmft-qe-symposium-january-8/
Okay well let me start by also from Paris wishing a happy New Year to everybody may it be healthy and prosperous and hopefully more peaceful and uh then let me thank the organizers uh for uh giving me the opportunity of St starting 2024 in this lecture series with a talk on Horns
Exchange in electrochemistry electronic properties of real life battery materials from a dynamical meanfield perspective a short disclaimer is in order because I’m neither a chemist nor a battery materials uh expert despite of what I’m going to pretend uh during the next half an hour this is a work uh mainly done by my
Former postdoc G on Sim who’s really the hero of what is going to come and in collaboration with DD sha and Jean Marie Tasco whoops and now I cannot move on ah yes so batteries battery compounds probably do not need much of an introduction we have witnessed the revolution in Mobile Electronics
Enabling us nowadays to run out with with our mobile phones or portable Electronics more generally we are witnessing the electric vehicle V Revolution which is starting and we are probably all putting High promises in uh the advances in Battery Technology for making use of renewable energy such as
Solar power or wind power for the energy transition the history of batteries uh goes long back actually as you probably know to VTA who put together the first Volta cell just a pile of zinc and copper plates in sulfuric acid electrolyte and then the oxidation of zinc and the reduction of hydrogen in
The sulfuric acid uh gives a voltage that you can use at the ends here however the problem of this kind of Technology was of course that this is not rechargeable this is already different for the good old lead acid battery where you have uh lad being oxidized and lad oxide being reduced in
The presence of sulfuric acid again to let sulfite this is now rechargeable but had serious drawbacks due to the use of sulfuric acid and of course also limited energy density you know the good old car batteries of a certain volume the development of the the lithium ion battery was honored by the
Nobel priz in chemistry in 2019 and in particular we highlighted three important discoveries related to that the first one was due to Stanley wittingham who showed reversible lithium insertion into inorganic compounds into in particular layout compounds such as titanium dulfi and then also later mpin D sulfide or SEL
So compounds that nowadays we would call famously the transition metal D chides um the cathode elect cathode material was revolutionized by John good enough enough who introduced the lithium Cobalt oxide as cut out material however the true Comm commercialization of the lithium ion battery at that stage was
Still hampered by the use of metallic lithium as the anode and that uh posed serious uh security issues due to denr formation which could be solved when Yoshino in Japan Akia yosino the third Nobel Prize winner actually proposed uh carbon-based ano that could get away from these problems and that led in 1991
To the first commercial lithium ion battery commercialized by Sony uh I don’t have to watch the chat Olivia right if there is anything serious you tell me that’s fine I’m we modifying the question okay um good no I’m not you’re moving so what is a lithium
Ion mety well uh it is a device where you have anode and code and in the uh discharge process you have lithium ions released from the anode material uh to the uh uh cathode material and at the cathode you have this uh oxidation relation here where Cobalt oxygen Cobalt
Oxide is transformed into the layered lithium Cobalt oxygen of good enough and at the an note you have the corresponding process the reverse is happening when you put a voltage and induce the charging process so discharge is a spontaneous Redux reaction and then the charging process uh leads to the inverse
Processes okay required specifications and this is really only very very partial list of what uh battery uh experts tell you uh the required specifications of an ideal catod material should be that it should be should possess an open framework structure be of course a source of
Lithium plus and of a lot of lithium plus as much as possible we will come back to this later to be of high voltage to ensure high density uh of the energy high energy density sorry uh to have the fast kinetics of the lithium diffusion and of
Course it should also be cheap easily available CH chemical elements and environmentally as innocent as possible thermally stable chemically stable and if now you go to the materials so the uh time onut example is the lithium cobaltate uh try were done on lithium nickelates but which were more or less
Discarded due to Thermal safety issues uh then the runner is nowadays the nmc or uh NCA here uh namely compounds where you have in the place of the transition metal in the place of the Cobalt uh several options nickel Cobalt aluminium or here nickel Cobalt manganese and this
Is indeed nowadays the most common cathod material for portable Electronics Cobalt free Alternatives have also be explored people want to get away from Cobalt for obvious reasons because of the mining issues and one candidate is to put manganese here which is indeed used in electric vehicles but has lower
Energy density and then uh there is research going on in various polyanion uh uh material combinations and of course also on the unor side also on nrct in and many things behind these dots recent developments include studies of what people like to call lithium Rich oxides an example is this one here
Lithium 1.2 nickel2 manganese 06 O2 and if you calculate quickly you realize that nickel O2 manganese o06 does not sum up to one so the missing point two is somehow on the lithium side here which which means that actually some of the lithium goes in the transition metal sites in
This compound and this is why we call this lithium Bri that holds current three the record for specific energy and that is thanks to precisely this issue uh that the lithium being on the transition metal site uh the charge compensation is done by the liant and that means that the oxygen lians here
Take part in the Electro chemical processes and in particular into the Redux activity which is a means to enhance the capacity of your battery material so what is this process that chemists call anionic Redux well it’s a reversible redox process that involves the lians and that leads to extra
Capacity this uh type of anionic Redux has been demonstrated in these lithium Rich oxides that I cited before but uh proved to have unfavorable cycling properties so some problems of voltage fate for example anionic reduxx is generally favored if you increase of course the liant content so if you lower the uh
Transition metal to Lian content ratio so for example if instead of having two oxygen for one maganese here you have uh lithium 2 manganese O3 and uh an redox indeed has a history in the chemistry Community uh it has been explored by Jean rousell in France
In the later 90s in sulfites and in particular in these uh titanium sulfates here where the titanium S3 the sulfur sorry the titanium per sulfite was thought of as a titanium 4 plus ion and then a sulfur 2 minus ion and a peroxy disulfur which that wouldn’t have two
Minus for two of the sulfus So eventually you take away electrons from The sulfur P shell in a physicist language this implies of course that you are in fact dealing with the charged transfer material where you have the Lian States close to the form level and you can take electrons from the top
Valence band formed by these Lian States however the chemist intution here involves also that you have this excess of the lithium inducing uh this process okay why is an grux interesting well you have already seen if you can get more lithium out of your battery uh you can enhance the capacity and uh
There is a kind of trade off between the voltage and the specific capacity here um in the end what is interesting is the area under this curve because voltage times capacity gives you the energy density uh of your material and that means you would like to infin uh
Enhance both the voltage and the uh lithium content the specific C capacity the more lithium you can take out the more capacity you have if you can by the tricks of the I gradu extend the area to this site here even if you have somewhat lower voltage you might still be
Favorable in terms of energy density okay going back to the list of materials that I’ve have shown you well as uh people here on Zoom for uh Quantum materials correlated materials what of course we are all striking with is that any of these materials involve partially filled transition metal shell
And that means when you want to do electronic structure calculation for those you need to take specific care to include the correlation effects so the methodologies that uh I think you are all more or less uh comfortable with include of course the basic density functional Theory but then also density
Functional Theory plus Hab Corrections and methods beyond that namely density function Theory combined with dynamical meanfield Theory so in the foll I will show you DFD calculations within the uh generalized gradient approximation in the flavor due to perber and anof and the PBE and GGA plus u calculations and
Then uh GGA Plus dmfd in uh GGA plus u charge self-consistent flavor well why is that we will be Trea treating uh quite complex unit salts and full charge self consistency with a full Quantum on impurity solve each step becomes expensive now that is why with gon Sim
We explored uh to do calculations where you uh self-c consist at the GGA plus u level you average over the spin and you take the resulting density as a starting point for the construction of your hamiltonian for the dmft so that it’s in fact a scheme that you can view as
Iterating at a started meanfield level and only at the last iteration using a full-fledged DMF Quant monado dmft solver to solve the dmft equations we do that with a spin independent fully localized limit double counting and with a standard parameterization of the interaction vertex in terms of th canamore parametrization for the 3D
Orbitals okay previous work on bettery compounds is numerous uh using DFT DFT plus u and even DMF and many people in the audience I’m aware of this have put a lot of sweat and work into these issues so I will not uh give full credit to all the
Works done that’s just too much my poor excuse is that I will not go to the lithium cobaltates nor to the lithium iron phosphates but to one that I think you have not worked on namely lithium 1.33 minus 2 y over 3 titanium 2/3 minus
Y/ 3 Iron y sulfa 2 with uh y determining the iron content of 1/3 so this is what I will dub in the following LT FSX so lithium titanium iron sulfa x with X either being zero for the lithium poor charged material or for x equal to to one for
The lithium Rich discharged compound and that is as you can guess already a layered compound the structure is here where you have a triangular lce structure in the typical uh transition mle ch ch diogenite structure piled up but uh with the sides here shared between not only titanium and iron but
Also some of the lithium and the Y here will adapt how much iron titanium lithium we will be having here okay so my further outline is I first will have to tell you what is now special about this compound why do we take these phone numbers uh then I will
Uh discuss the electronic structure of the end members for uh lithium rich and lithium poor compositions x equal 1 and x equal zero I will do that at the special point of yal 1/3 for the iron compound for reasons that I will discuss I will discuss the role of H exchange
For the physics and uh conclude a little bit okay so why these phone number compound here well you may have realized that if I take out the iron so y equal zero and I do a little bit of algebra here uh my lithium 4/3 titanium 2/3 sulfat 2 is actually nothing else than
The iso structural analog of lithium 2 manganese O3 that we have seen before in the uh lithium Rich oxides so we are heading of course here again for this question of the anionic Redux except that now we have replaced the oxygen by sulfur sulfur is less electronegative so
The Lian States move closer to the buy level and that means the anionic redox process should become easier however in the pure compound here the lithium 2 titanium S3 titanium is in the for plus configuration and the whole thing is actually electrochemically inactive so the idea of introducing now
The iron into the compound can be thought of as taking the lithium to Titanium S3 where you replace some of the titanium titanium 4 plus by Iron 2+ and then you adjust the charge by just adjusting the lithium content of the material so this is what is actually
Happening when you do these pH number compounds you add a little bit of iron and then you do it by adjusting here and that indeed induces now low energy states close to the firm level which can be expected to be of iron 3D and Sol for
3B 3p character and that gives us a model system for the I ionic Redux that the chemists are interested in so in a schematic picture when you start from an oxide one of the classical ones here the lithium manganese oxide um and you move to the sulfites overall you shift closer
To the ful level you have in the first place the empty titanium uh shell here and then by adding the iron you have iron States so this is just a Ben structure picture no correlations yet uh you have ird States here at the firy level together with sulfur non-bonding
States at the top of the valance band and note that here everything is uh uh drawn with a reference to a lithium lithium plus anode and not with respect to the F level which of course would be somewhere then here okay so what happens experimentally well this for number compound has been
Synthesized indeed for different uh iron contents and here is the experimental result for the capacity as a function of the iron contents so of the Y and that gives a curves that goes like this here you see my my mouse right yes um so you see that the initially non
Electrochemically active uh iron free lithium titanium sulfite becomes indeed rapidly activated and uh then essentially goes via a maximum uh to a line which would be the theoretical capacity if you can take all all all the lithium that you have so you actually come close to that
For some values and in particular for the value of y equal 3 which is close to the 1/3 that we will use later on precisely for that reason not also that interestingly what is drawn here is the theoretical Capac it that you would have if you were only doing Redux processes
Between iron 2 plus and iron 3 plus which are believed chemically to be the ones happening if you would also if you were also dealing with iron 2 plus going all the way to iron 4 plus which chemists believe for good reasons not to be the case then you could enhance the capacity
But not to the value that you have here so that means this area is already in indeed showing that you are doing anionic Redux in this compound so experimentally we can um note the remarkably high capacity 250 here for this Y3 uh 250 amp per hours per
Kilogram and in this state most power experiments show that you indeed as I mentioned fully reversibly oxidize between two iron 2 plus and 3+ and also that you have uh iron 2 plus States in a high spin configuration on the positive SES the good news for camons is that now you
Indeed have better uh cycling properties so you fix some of the Prov that were seen in the oxides however this comes at the price of a lower voltage because of course with the states being closer to the family level that also means that you have uh voltage it’s rather of the order
Of 2.5 electron volt instead of four okay so now let’s switch to calculations so this is just a plain vanilla uh GGA calculations generalized gradiant approximation calculations for the two end members so the one that I call x equal 0 and the x equal one compound here um overall you see the big
Chunk of sulfur States here in Green in both plots you have the iron D States and the titanium in Orange you confirm that the titanium here are empty you see that the iron D interestingly here in the fully lithiated compound are gapped and that is actually just the splitting between the fil t2g
Manifold which has now six electrons and and the empty EG States here in the delithiated compound you have a D5 nominal configuration on the irons and that means necessarily you go back to a metallic State you have a t2g five uh low spin uh and thus not completely filled t2g
Shell also plotted are in red here the sulur P state Associated to octahedra where the central ion is not a transition metal but a lithium so those are the ones that the chemists are interested in because of their non-boring character and you see that indeed there are quite a few of
Them at the top of the valance here uh in the uh lithiated compound okay let me summarize a bit schematically what we have seen here so we confirm empty titanium sh the sulfur down here but reaching up to the firmy level in the delated compound and uh the uh low spin configuration
Here U and uh a little bit larger splitting here okay now switching it you can see it better and I give you additional information that the t2g EG splitting is indeed uh smaller in the fully lithiated compound than in the uh delithiated one one electron volt compared to 1.8 nearly so quite large
Splitting okay from the electron counting you also arrive at the uh nominal configuration of the sulfur which is missing here 1/3 of an electron so having empty States uh close to the form level here and that is of course already the sign of the any credits okay
Now we can do this a little bit more in a more refined fashion uh the upper panel is still the GGA spin polarized GGA actually uh unders what we just achieved namely the high the the low spin uh band insulating uh lithiated compound here now becomes metallic again
Because you uh push uh electrons into the EG State um GGA plus u opens uh the Gap again um however has a depletion also here in the delated compound moreover this is not noted uh if you look at the magnetic moments the uh delated compound has a Magnetic Moment of 2.3 muor which
Is not compatible with the experimentally observed low spin configuration in that compound overall of course we know that GGA plus u in this case will probably underestimate fluctuations so we want to go beyond and to see what actually dmft is giving us this is GGA plus dmft again for the lithiated and the
Delithiated compounds and now you see that actually interestingly we reopen the Gap here uh in the lithiated compound and we found a mod insulator with a high High spin High spin configuration um however in the so this is for the uh the D6 configuration or in the D5 configuration here we rather have
A Peak at the firmy level and note that this is a peak both in the iron uh densis or spectral function and also the sulfur States here again so you see a strong covalency in both uh compounds but even stronger actually in the delithiated metallic compound so we
Switch actually when we do the Redux process from a high spin mod insulator to a low spin metallic system this is the redox transition so now we can look what we really gained compared to LDA plus u so what is the what are the fluctuations doing that we
Have added here in the dmft well uh solving D mft equations with Quantum mono has the advantage that you can directly do fluctuation statistics I think thas will come back to this much more in detail so what we draw here is just the probability of visiting configurations with a given quantum
Number and in the upper row this is for the uh spin component and in the lower panel just for the number of electrons on the iron 3D Shell and again left hand side for the lithiated for the fully for the lithium Rich compound and right hand
Side for the poor compound and what you indeed see here is the uh Peak so just focus on the blue curves which is for the let’s say realistic H coupling value uh you have here a peak around indeed a value which can correspond to the highest spin configuration whereas in
The delated compound the distribution is really Broad different configurations all contribute more or less equally also in the uh electron numbers you have relatively narrow contribution here but in the delated compound you have substantial contributions even here from quite low and quite High uh electron numbers on the
Dell okay having s that we are treating with a with a uh metallic compound for the lithium poor version we can of course also now investigate the properties of this metal from the point of view of a dmft person of a correlated metallic system and in particular what
We have looked at here is the Quasi particle residue so the weight of the Quasi particles in the metallic State here as a fun function of the value of the H coupling and what we find is that the value for J equal zero would be here about seven something or 0.9 depending
If you look at the p2g orbitals or the EG orbitals but when you switch on finite hun coupling this value drastically decreases depends much more on the H coupling than on the U Dash lines and solid PL differ U and uh goes actually to relatively low values in
Particular for the more occupy t2g orbitals here so that means that actually for realistic values of J which are rather around here than here the Quasi particle residue becomes as small as 02 something and that means that we are indeed in a quite strongly correlated uh metallic regime but again
Driven by the Huns coupling J so what in the literature people like to call h metal we have yes five minutes yes yes I’m I’m I’m quickly done thanks okay we have um calculated uh the temperature dependence of the spectral function which shows the expected just broadening and without habot bands corresponding to
The uh scenario of the h metal okay then finally we have calcul ated the voltage so the voltage can be obtained just by a combination of the total energies of delithiated and lithiated compound and the pure lithium and so what is given here now is the uh ggl value spin
Polariz GGA and as a function of again uh HS coupling the voltage um in GGA plus dmft so in GGA plus dmft again we have a strong dependence on the H coupling we approach the experimental value which is somehow as I mentioned 2. just below 2.5 so 2.48 something which
Is nearly reached for the relatively large uh values of J but what is even more interesting is the comparison of the shape of this curve voltage as a function of winds coupling with what you would get at the atomic limit so if we calculate that thing just energetics in the atomic limage and
Extract the voltage we get actually a shape which is very similar a kind of vshape with a flattish slope here and a more steep uh increase here and that is essentially given by uh energetic uh balance between the crystal field splitting and the Hun coupling of course which determines this
Thing okay so what we okay no sorry last Mark still uh now we have uh deicated where the uh J dependence of the voltage comes from and since we are dealing just with total energies here we can of course look if this comes from the kinetic energy part or from the Kum
Energy contribution to the uh total energy and the two voltages so the contributions of the two parts to the voltage are drawn here separately in Orange the kinetic energy contribution to the voltage and in blue the potential one and what you can see from that is that indeed the dependence stems more
From the potential energy for from the kulum uh part to the total energy and in particular the increase here is uh of course as anticipated here already due to the coolum interaction and in particular the H coupling okay with this uh I conclude so uh cathod materials for battery applications are correlated electron
Materials but with potentially quite complex unit cells so in this case we applied here uh GGA plus dmft scheme where we cheated on the charge self consistency by helping us uh with the GDA plus u method just to iterate on the density and then the applic to the
Lithium Rich sulfites the ltfs Z and one yield respectively a high spin mod insulator and a low spin correlated metal that means the Redux driven spin State transition coincides with a M transition so overall HS coupling determines the energetics of the compound the physics of this compound
Including the voltage and uh the uh okay I have not insisted on that too much the strong iron sulfur calent is crucial we actually did analogous calculations just for the oxide and in that case you would have both materials both end members in large spin uh states with large moments
So one can conclude that both the the choice of the onion um is that the choice of the onion is essential actually for optimizing battery properties such as capacity but also operating voltage of course and finally that means that battery materials are an intriguing and maybe important playground for collated
Electron physics and that in turn also electronic structure tools nowadays can maybe be put at the service of the energy transition thank you very much for your attention very much for the for the next talk so we are now uh for questions um I think onto has a
Question yes now yes yeah can you hear me now yes yes first I’d like to wish a happy New Year and a good start for this Symposium to everybody previously I was cut off from video and sound so I couldn’t do this in person and thank you
Very much zilka for this beautiful talk uh also pushing the boundary of applicability of the mft I actually have a a question so you emphasized both the importance of anionic ruxx meaning the contribution of the liance the capacity and the importance of the hon cing which promotes the high spin configuration but
Is there a logical connection between the two namely is increasing the hon cing also or modifying the hon cing also affecting the degree of liant Redux or somehow these are disconnected aspect um okay that’s a difficult question um it’s an overall plot because of course the um if I go go
Back here the the question of the strong hybridization is what enters uh here in the energetic uh positions of the states so you have in in particular here for example the large spin splitting um which eventually avoids the high spin uh configuration here um the um and then the second question of
The position of the the sulfur so um they are connected I would say okay they are connected in the sense that the strong Co valency that the sulfa introduces two things the strong Co valency because of the extension and also uh the relatively High position so it’s hard to have one without the
Other um but I wouldn’t say that it immediately helps and perhaps as a footnote to my question so you emphasize that in the metallic state right which is the lithium po State the histograms of states is very broad over different CH States but is it such that within each
CH state it is still the high spin configuration that dominates so that would qualify this state to be called a hon metal um no no no no no no um it is in the metallic uh State rather the low spin configuration so aha I see
So if we look at within each n value of n right we can decompose we can make histogram for separate multiplets you seeing it is not the highp multiplate in each charge configuration that dominates no no but nevertheless you have the phenomenology of of this year so in that
Sense that we say hun metal it’s not in of really having iceb configuration yeah okay thank you thank you thank you okay uh for some reason Andie would like to ask a question but he cannot technically so he yes uh given the question to me so I’m going to read the question
Um I understand that an important figure of Merit is the speed of charge and discharge does the many the many body electronic structure be on this issue oh yes that is one of the questions Andy sorry that I avoided um because I’m not sure that I can say anything intelligent on this so
Indeed you’re right this is one thing that the chemists are very concerned with um but at this stage we do not have any theoretical put on the kinetics okay thanks so on actually two questions I’m reading this next and then we take next question I understand that stability over many cycle is an
Important issue uh okay that’s a many body structure this issue so stability of a many cycle um yes uh somewhat more I would uh think because uh the stability over many cycles goes along with the energy barriers uh of close compounds so for example um if you have in the oxides for
Example in some cases you have oxygens being oxygen gas being freed or something like that and that is of course a thing that uh in in principle can be assessed by the energetics and the calculations of the kind that you can do here we we didn’t do that but
Uh I think this is more okay in so next question cast you had a question yeah thank you Olivier and and very inspiring talk Sil very nice topic so I I wonder about the Hun exchange so so you said it’s Point N so so sometimes
You have something like 0. n or one if you have a density density kind of H exchange but it’s somewhat lower 10 or 20% if if you take the full su2 symmetry into account because the singlet and triplet splitting is is is larger in the su2 form so so is this9 including this
Effect or or is it the be CPA value from a density density kind of uh D calculation here we are doing uh density density interactions ah okay I should have noted that so whenever we did not calculate uh the evolution as a function of J we
Fixed 0.9 as the value that uh you would believe to be the realistic one okay then in this framework it’s the the right value okay interestingly um one could speculate because the calculated voltage would even suggest here that indeed it has to be at least 0.9 but
Maybe there are of course also other effects so it has to be a large HS coupling okay yeah thanks thanks and happy new year thanks same for you m uh yes the last question can you hear me yes yes hello yes thanks a lot for the very inspiring uh calculation on this
Important materials um so in the beginning you mentioned that you what makes this material special is that you’re starting to oide uh the the sulfur orbitals um but you your dmft only included like the the the de orbitals of the iron site so when but when the in your calculation
Do you see this contribution from the uh from The sulfur orbital coming into play yes now uh we we do put a s energy only on the iron orbitals but we have the full States including sulfur ird titanium in the calculation so that means and in particular of course also
Uh already at the initial stage when we prepare the hamiltonian for the final iteration from the GGA plus u there you have also charge transfers between the so it’s it’s when you build your your localized orbitals that this is where the mixing is coming in yes yes
Absolutely so you you have a hamiltonian which has Everything In It’s just that the self energy applies only to the R&D States okay so it’s that the GGA plus U part that you see this mixing coming in into Play Already yes yes but also later
I mean when you look in the dmft uh for example if you see a spectral function like that here you you understand that here indeed you have states which are actually uh sulfur iron hybridizing okay yeah this is independent from the fact that I treat only the irons as correlated the others
Are there the other are there okay thank you yeah thank we have time for one last quick question byul yeah do you hear me yes yes okay I I just have a simple question when you do you did calculations for two two two composition positions these in these compositions
The the unit cell was well defined or did you have to to do fractional occupancies um now in this composition the unit cell is luckily well defined and that’s why we did actually two okay um we had the experimental uh lettuce parameters but then we had to optimize or to find the internal
Positions but the the ratios were uh the lucky ones that we chose like that okay it would be difficult to to do your one third feeling for instance yes yes yeah you see asking that because thinking to Cate it’s okay but well if I have time I I’ll have a I’ll I’ll drop
At the PO technique and discuss with you about that okay with pleasure all right uh thank you very much um we uh Antoine you wanted to say yeah I just want to make a very quick comment perhaps to to clarify the the question also the discussion that Michelle kot started so
Zil just to make sure I understand so the calculation is done using all states right including the Lian States and everything and so you use what we call a big window right and and self energy is only put through the mft on the D States so it it’s not only through the choice
Of the vaner functions and so on that the erization of ligant is actually taken into account it’s through the whole charge redistribution between ligant and transition metal since you do handle the whole big window electronic structure right absolutely yes yeah wanted to try High that’s what I what I
Tried to say yes thank you sorry for repeating thank you all and thank you Z for the the very nice talk we now have to move to the second talk uh