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yeah hi everyone I'm site from you and

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our today I'm going to talk about

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computational ir spectroscopy for

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detection of metal of fullerenes in

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space specifically a metal inside c60

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and that metal could be lithium sodium

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or potassium but generally in a research

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group we are trying to answer two

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questions what is out there and how it

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got formed so today I'm going to talk

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about what part here are some outlines

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the first I'm going to talk about the

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goal of this project and I give you

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briefing introduction about fuller is in

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space and computation ir spectroscopy

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and at the end I show you some

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preliminary results and conclusion at

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the end so the goal of this project is

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to get computationally to obtain ir

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spectra for these metal offerings

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compound mention but it we have to

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include anharmonicity and wide why we

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are looking for computational spectra

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because these molecules are very hard to

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purify and that's why we don't have

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experimental data available so we are

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trying to make or model it

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computationally and the reason we have

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to include on harmony city because the

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study studies have shown that this into

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the interaction between metal and carbon

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cage is very weak

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and we spare we expect shallow potential

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that's why we have to include on harmony

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city in our spectrum and for to achieve

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these goals we have few steps to follow

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first of all we have to locate the

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position of that metal atom inside the

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cage and find out all the possible

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isomers and then get the harmonic

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spectra and then to include on harmony

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CDV we need to use time dependent and

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time independent methods for as for time

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independent method we used vs CF or

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vibration of self consistent method and

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for time-dependent we use molecular

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dynamics and this is the telescope this

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is called a spitzer and this just

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collects information or signals in IR

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region infrared region and what

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eventually we're going to do is get our

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spectra and then compare our results

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with the data coming from this telescope

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and then if they match we can prove the

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presence of metal of fullerenes in the

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space and that's how they discovered c60

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and CS 70 for the first time in 2010

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kami and coworkers modeled see 60 and 70

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70 this red line is c 60 they model e

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computationally and the blue line boo

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spectra is c 70 and then the black

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spectra is coming from a spitzer so they

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matched it and they proved the presence

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of cccc 60 and c 70 in a young

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netru nebula so-called tc1 and a few

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years later this Duncan co-workers they

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found they basically proposed that nom

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metal of fullerenes also can be formed

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in the same region as easy as easy as

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fullerenes and they basically could

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synthesize am a sodium inside the cage

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of c60 with by under highly energetic

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conditions in oxygen and hydrogen rich

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and stellar condition and I briefly

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talked about my metal but the

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methodology I used and computational ir

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spectroscopy I need to be faster so the

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very first step is getting harmonic

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spectra and but then we basically

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displays the atoms around their

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equilibrium positions and we get the

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force constant and calculate the

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frequency and this is as I mention this

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only includes harmonic frequencies but

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we have time independent vibration of

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self consistent method we will be sample

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energies along the harmonic modes and we

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get the vibrational energy levels and

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wave functions and we can basically get

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the overtones combination bands and

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coupling between modes basically and for

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time-dependent methods we have molecule

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dynamics there are two codes for that

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md's molecular dynamics and DRC's

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dynamic reaction coordinate this is a

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basically classical trajectory based on

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the quantum potential energy surface and

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be first we have our initial conditions

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we have time and energy be putting

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system and we use a Fourier transform of

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time auto correlation function to go

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from time demand to frequency domain and

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I know you don't care about these

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equations but the first one is the free

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and fourier transform for one trajectory

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and the last one is for multiple

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trajectory when you take average over

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multiple trajectories if you have

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questions later I can answer but these

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are or computational details that we

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used again you don't care but tag so

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first we got these structures the

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isomers of different isomers of sodium

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at c60 and then doing future we're

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trying to extend it to other metals as

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well but this is related to different

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symmetries of different positions of

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sodium inside the cage with the relative

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with their relative energies and this is

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the first spectra which is related to

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harmonica spectra and the comparison

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between those different structures and

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as you see here just there is one thing

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to mention here that the peaks related

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to the movement of sodium inside the

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cage it has a redshift for c1 symmetry

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and this is where due to the loser bond

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of sodium to that structure because of

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the position of sodium inside the cage

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and here I have a comparison between c63

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sixty- and sodium at c60 c6 he has only

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four fundamental piece but when we have

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c 6 t minus did

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the extra electron can which has a

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resonance inside the cage can break the

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symmetry and we have much more peaks but

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you can see the peaks for the blue sorry

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the red peaks and the yellow peaks are

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matched because we trying to show here

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that that extra electron from sodium

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radical actually transfers to the cage

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and does the same thing as that minus

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electron that the extra extra electron

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is 60 minus and we have basically the

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same peaks except for some extra piece

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for sodium acetate is equal and that's

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due to the movement of sodium inside the

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cage and this is the last result I've

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I've got so far for hall which is

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comparison between harmonic and on a

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harmonic which on harmonic is coming

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from vs CF and basically you see here

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you see a red shift for on harmonic

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Peaks compared to harmonic ones for from

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the vs CF met and we also try to ok we

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also try to use model molecular dynamics

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and first for a simple molecule like

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water and that showed us this and not

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only can provide us harmonic or normal

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modes but also can give us overtones and

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overtones and combination bands as you

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see here but then we apply this in our

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system we could get only lower

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frequencies but not higher ones and we

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think it's due to the fact that we only

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used one trajectory not multiple ones so

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we are trying future to use multiple and

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take the average over and as a results

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ir spectra for these compounds

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as I mentioned are very structure

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structure of dependent and on one on

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harmonic frequencies show the redshift

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compared to harmonic one and in future

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in order to sample a complete the

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spectra we need to first of all include

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couplings between modes and also we need

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to get put higher temperature or system

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and also we need to consider multiple

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trajectory instead of one and then we

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can extend our work to other method of

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fullerenes thank you okay thank you very

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much for our presentation I saw you have

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different entries for turbulent

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symmetries of metal at c60 it is as any

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I see your connections to differ

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energies barriers for this different

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symmetry oh yes yes I didn't do I've

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been there is they have different

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energies but we don't know about the

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barrier that as I shoot here in this

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slide oh okay yes first not yeah yeah

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and the energy difference so if there

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are relative energies but if this is 0

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this is 72 this is 73 but this is what

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we have found so far they might be more

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I guess I was just wondering um so what

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is the nature of the coordination or the

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bonding of the metal within the cage is

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it ok so the global minimum of which

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that we have found so far is the sodium

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is in between it's closer to the wall

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and it is in between pentagons and

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hexagons that's the global minima we

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have found so far but I'm doing more

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calculations to find more structures ok

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yeah I'm just wondering how you did the

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exploration of the minimum

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configurations of sodium in the bucket

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ball ok so first I picked some

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symmetries c1 c2 VCS c5 ec3v and then I

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did geometry optimization I found the

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structures and the idea the Haitian

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calculation at the top of that if they

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have imaginary frequencies I distort

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them along that imaginary frequency to

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get equilibrium or actual minima but so

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far only these three structures have no