A Lecture Proposed By SPP Molekular Magnetismus (DFG)
A lecture proposed bySPP Molekular Magnetismus (DFG)How molecules go magnetic Michel Verdaguer, Françoise Villain,Ruxandra Gheorghe, Fabrice PointillartUniversité Pierre et Marie Curie, Paris
Why experiments ?because -experimentexperimentexperimentexperimentarises curiosityis speaking is demonstrating can be beautiful !Bad Durkheim, SPP Molecular Magnetismus (DFG) 6-9 may 2007
Whyexperiments inmagnetism ?because - it is an important phenomenon - it arises curiosity - it needs to be demystified and explained- and experiments are beautiful !
Whyexperiments inmolecular magnetism ?because - our live relies on it and nobody knows - it is badly known or unknown - it can be explained simply - and experiments are beautiful !
Goals ?1) Citizen awareness2) Attract good studentsto our discipline3) Here : convincing you thatsuch experiments are possibleto realize during Science Festivals .
Comments about a possible LECTURE(abridged )Bad Durkheim, SPP Molecular Magnetismus (DFG) 6-9 may 2007
Publicity Campaign,Campaign, Barcelona,Barcelona, 2004
This is NOTthe questionor not ?
Everything is magnetic How ?
Everything is magnetic How ?Pierre CurieLectures NotesFonds documentaire ESPCI
Everything is magnetic How ?Pierre CurieAnnales de Chimie7ème série, V, 1895, 289(Thèse de P. Curie)Fonds documentaire ESPCI
DiamagneticMagnetParamagnetic
macroscopicworldatomic ormolecularworld« wonder »worldmacroquantumCais do Sodre Metro Station Lisboa, Antonio Dacosta
Everyday lifeis full of useful magnetswhich traditionally take the formof three-dimensional solids,oxides, metals and alloysMagnets in our worldWe are in a real world, at our size
M. FaradayCourtesy Prof. Frank James, the RI
macroscopic worldA pioneering experimentby M. Faraday« Faraday lines of forces »about magnetic fluxNSCourtesy Prof. Peter Day, the RI ; See also :The Philosopher’s Tree,The Institute of Physics Publishing, Bristol, 19999
A magnet creates a magnetic field« Lines of field »
What is a magnet ?What is NOT a magnet ?Magnetizationmacro
Magnetization :macroHow behave objectsin a magnetic field ?Remnant MagnetizationMagnetization M(how do they become « magnetized »?)MagnetCoerciveField« hard »Applied magneticField H
Tout est magnétique Comment ?Pierre CurieAnnales de Chimie7ème série, V, 1895, 289(Thèse de P. Curie)Fonds documentaire ESPCI
Everyday lifeis full of useful magnetswhich traditionally take the formof three-dimensional solids,oxides, metals and alloysCurie Temperaturemacro
The magnetic moments order at Curie temperatureA set of molecules / atoms :TCkT JMagnetic OrderTemperatureSolid, Magnetically Orderedor Curiethermal agitation (kT) weakerTemperaturethan the interaction (J)between moleculeskT J Paramagnetic solid :thermal agitation (kT) largerthan the interaction (J)between moleculeskT J
Magnetic ordering : Curie Temperature a demonstrator
from macroscopicto atomic worldlooking closer to smaller and smaller magnetsNN SS many sets of« domains » manysets ofatomicmagneticmoments
How magnets behave ?Domainsmacro
Domains
Physics : MacroscopicpermanentmagnetsS 10 2 0Mesoscopicmicronparticles101 0nanoparticles108106multi - domainnucleation, propagation andannihilation of domain walls105Nanoscopicmolecular individualclustersspinsclusters10410310210magnetic momentquantum tunneling,quantizationquantum interferencesingle - domainuniform rotationcurlingmacroquantum1M / MS0Fe 80.7KM / MS1M / MS1001K-1-40-1-201020µ 0H(mT)400.1K-1-1000100µ 0H(mT)-10µ 0H(T)1Wolfgang Wernsdorfer, Grenoble
Everyday lifeis full of useful magnetsMagneticEarthCompasses1600William GilbertDe Magnete
Jan van der Straet (Giovanni Stradanus), Bruges, 1523 ; Florence, 1605Nova Reperta, vers 1620-1630 , 14 planches gravées par Jérôme Wierix at Adriaen Collaert,éditées par Philippe GalleCalcul de la longitude, Burin 22 x 28 cm around 1600 Inv. n 11786
Compasses, Jiangomen station, Beijing
The fascination ofmagnets on children« A wonder of such nature I experience as a child of 4 or5 years, when my father showed me a compass. That thisneedle behaved in such a determined way did not at all fitinto the nature of events which could find a place in theunconscious world of concepts (effects connected withdirect « touch »). I can still remember – or at least believeI can remember – that this experience made a deep andlasting impression upon me.Something deeply hidden had to be behind things. »A. EinsteinQuoted by Livingston, J. D. In Driving Force: The Natural Magic of Magnets.Cambridge, MA: Harvard University Press, 1996. ISBN: 0674216458.
Everyday lifeis full of useful magnetsToysmacro
Everything is magnetic thanks to electrons
Origin of Magnetism the electron *I am an electron rest mass me, charge e-, magnetic moment µBquantumeverything, tiny, elementary* but do not forget nuclear magnetism !
Origin of Magnetism« Orbital » magnetic moment« Intrinsic » magnetic momentdue to the spinµorbitals 1/2eµorbital gl x µB xlµspinµspin gs x µB x s µBquantumµtotal µorbital µspin
Dirac EquationThe Principles of Quantum Mechanics, 1930Nobel Prize 19331e 2ehp4eh 2eh(E' e! )" [(p A ) # % A& !&# ! % p ]"2mc2mc8m 3c 2 8m 2 c 24m 2 c ry/PictDisplay/Dirac.html
About what are we speaking ?Representations,Models,Analogies
Analogy : spin and arrowPaul Klee, Théorie de l’art, Denoël, ParisAn isolated spin
Electron : corpuscle and waveΨ Ψ ΨWave functionHokusai, the great wave in Kanagawa
Electron : corpuscle and waveWave function or « orbital » Ψn, l, ml l 01s23pxyzy,z,xx,y,zdzyxquantumangular representationyx
quantumElectron : also an energy levelEnergy Diagramme (« ladder »)OrbitalsEnergyVacant, emptySingly occupiedDoubly occupiedNO MORE than TWO !Principle 1 : fill from the bottom (aufbau)
quantumElectron : orbital and spin !UpSinglyoccupiedDown« Paramagnetic »mS 1/2R!*Nitrogen oxide NO ONCONN O NitronylnitroxydeC N !*O
quantumElectron : orbital and spin !DoublyoccupiedS 1/2 - 1/2 0« Diamagnetic »Principle 2 : no more than TWOelectrons per level (orbital)with different spins !(Pauli’s exclusion principle)
Moleculesare most often regardedas isolated, non magnetic, creaturesDihydrogenquantumDiamagneticSpin S 0
N2 Diamagneticmacro
Pouring liquid dinitrogenliquid dinitrogendoes NOT stickdiamagnetic
the dinitrogenis a diamagnetic moleculeNAEpxN-NNBpy pzdiamagnetic, spin S 0All electrons are paired in bonds, very stable molecule
when dioxygen is in its ground stateit is a triplet (spin S 1)and its reactivity is weakParamagnetic O2macroLiquid O2
liquid dioxygendoes stickO2 is paramagnetic
the dioxygenthat we continuously breatheis a magnetic moleculeOAEpxO-OOBorthogonal πmolecularorbitalspy pzparamagnetic, spin S 1Two of its electrons have parallel magnetic moments that shapesaerobic life and allows our existence as human beings
when dioxygen is in an excited stateit can becomes a singlet (spin S 0)and strange reactivity appearssometines useful (glow-worm )quantumSinglet dioxygenLuminol Light
quantumdioxygen singlet (spin S 0)OONHONHNH2OHONH2NNOHluminolmacroglow-worm Documents from Nassau and Alvarez
More complex molecular frameworkscalled metal complexesbuilt from transition metal and moleculesare able to bear up to five or seven electronswith aligned magnetic moments (spins)
Il sistema periodico (Primo Levi)1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18p Elementss ElementsHHeLi Bed Elements : transitionNa MgK Ca ScB C N O F NeAl Si PS Cl ArTi V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br KrY Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I XeRb SrCs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At RnFr Ra Ac f ElementsCe Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb LuTh Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr44,956 47,867 50,942 51,996 54,938Sc21Ti22V23Cr2488,906 91,224 92,906 95,94Y39Zr40Nb41Mo42Mn2555,845 58,933Fe26Co2758,693 63,546 65,39Ni28Cu29Zn3098,906 101,07 102,91 106,42 107,87 112,41Tc43Ru44Rh45Pd46Ag47Cd48138,91 178,49 180,95 183,84 186,21 190,23 192,22 195,08 196,97 200,59La57Hf72Ta73W74Re75Os76Ir77Pt78Au79Hg80È bello raccontare i guai passati
Transition Elements5 d orbitalsEUnpaired ElectronsPartial uantum
Puigcerda,Puigcerda, Cerdanya,Cerdanya, may 31, 2006
Mononuclear complexML6Splitting of theenergy levelsLLLLMLLzyxE
Electrons WANTED !An indirect manifestationof the presence ofunpaired electrons :the colour
Complexes of transition metal ionsoften display beautiful coloursessentially to d levels splittinghνColours in waterGeometrical ChangesSpin Changes
The complexes of transition metalpresent often delicate and beautiful coloursdepending mostly on the splitting of the d orbitalshνquantumhνmacro
Complexes of transition metal ionsoften display beautiful coloursessentially to d levels splittinghνhνhνhν S 0quantumColours in waterGeometrical ChangesSpin Changesmacro
Electrons WANTED !A direct manifestationof the presence ofunpaired electrons :the magnetismor interaction with a magnetic field
How large is the splitting ?EnergyHigh spinL H2 O[C2O4]2-egx?Weak Fieldzy!octyzxIntermediate Field Strong FieldTemperatureDependentSpin Cross-Overz2x2-y2Low spinL CN-xyzxxzyyzt2g
Curie LawCurie BalancePierre Curie, 1900 ParisχMT Constant
S 0S 1/2K4[Fe(II)(CN)6]Diamagnetic,spin 0K3[Fe(III)(CN)6]Paramagnetic, spin 1/2(NH4)2Fe(II)(SO4)2S 2Paramagnetic,spin 2
Magnetization : how objects behavein a magnetic field ?Magnetization M(how they become « magnetized »)magnetparamagnetic M χ H, χ 0Applied magneticfield Hdiamagnetic M χ H, χ 0macro
Playing with ligands,the chemist is ableto controlthe geometryand symmetryof complexes (colour, magnetism)
Co(II)Cl2, 6H2O : from octahedral to tetrahedralHeatCo2 2 Clmacro H2O Cl-- Clquantum
Playing with ligands,the chemist is ableto controlthe spin stateLisboa University, October 9, 2006
Hysteresisallows bistability of the systemand use in display, memories Spin and colour changesmacro
[FeII(H2O)6]2 pale greenS 2macroquantumFeII(o-phen)3]2 bright redS 0
Low spin, chiral, FeII(bipyridine)3]2 ΛΔ
Playing with ligands,the chemist is ableto controlthe spin stateLisboa University, October 9, 2006
Spin Cross-OverA Fe(II) « Chain » with spin cross-overRRNNNNNNNFeNNNNNNFeNNNNFeNNNNNFeRNNFeN NN4 NNNNRRTriazole substituted Ligand (R) ; insulated by counter-anionsMany groups : Leiden, Mainz, Kojima, O. Kahn, C. Jay, Y. Garcia, ICMC Bordeaux
Samplecoming fromLow TSamplecoming fromHigh TTransition Cross-over Demonstrator by Jean-François LetardThe very samples presented were synthesized by students in Paris during practical worksCourtesy Prof. C. Roux, C. Train, A. Proust
Spin Cross-OverBistability DomainRoom Temperature3!M T / cm3 mol-1Red0250TCTC300WhiteT / K350The system « remembers » its thermal past !O. Kahn, C. Jay and ICMC Bordeaux
Then, memory ?« It is an essential character of living being that thesensation leaves traces.There is nothing comparable in material worldIt is a real joke to name « memory » the hysteresisphenomenon. » Paul Langevin, Discussion sur la matièrematière vivante,10ème semaine internationale de synthèse, 1938, PUF, 1943, 219-223
From the molecule to the material and to the device O. Kahn, C. Jay and ICMC Bordeaux
O. Kahn, Y. Garcia, Patent
May we go furtherand dream of molecular magnetsi.e. low density,biocompatibletransparentor colourful magnets ?
Do the chemistsknow howto align the spinsof electronsin molecules,parallel or antiparallel ?
to get magnetic compounds Understanding why the spins of two neighbouring electrons(S 1/2) become :antiparallel ?or parallel ?S OS 1SingletTriplet
J 2 k 0if S 0OrthogonalityO2HundESETJFerro 4ßS 0if S 0; ßS kOverlapETESJAntiferroH2Aufbau
Tell itwith flowers(find the orbital)isolatedOverlap (π)Overlap (σ)OrthogonalityFlowers from the gardenof the Gulbenkian’s FoundationLisbon
Exchange interactions can be very weak EnergyExchange interactions order of magnitude :cm-1 or Kelvins « Chemical » bondsRobust !order of magnitude : 150 kJ mol-1 Michelangelo, Sixtin Chapel, Rome
Please, avoidpairing electronsinto bonds
Avoid NO2 Dimerisationmacro. to pairthe « magnetic »électrons
Interpretation(s)Thermodynamics (Le Chatelier )1N2O4Equilibrium : 2 NO22 HeatcolorlessBrownOrbitalOONNOOOOONPairing of electrons, bondingDIA-magnetic !NO
A beautiful artefactWhen some residual NO is present in the vessel :1Reaction : NO NON2 O 322BrowncolorlessBluegreen
Cu(II)LigandCu(II) 5 ÅOrbital Interaction
ALigandBWhich ligand ? Why not Cyanide, CN- ?Museo nacional dos azulejos, Lisboa
C NCyanide LigandFriendly ligand : small, dissymetric, forms stable complexesWarning : dangerous, in acid medium gives HCN, lethal
Cr(III)Ni(II)Dinuclear µ-cyanoheterometallic complexesNB : A dissymetric ligand helps to get stable heterometallic complexes « Birds of the same feathers flock together »
Polynuclear complex,3-synthetic strategy2 9 6Hexacyanometalate “Heart” Mononuclear ComplexLewis BaseLewis AcidmacroPolynuclear Complex
macroFerromagnetic Paul KLEEErosFerrimagnetic Nocturnal separation, 1922
High Spin Heptanuclear ComplexesC rC u6S 9/2HexagonalR -3a b 15,27 Å; c 78,56 Åa b 90 ; g 120 ; V 4831 Å3C rNi6S 15/2Hexagonal R -3a b 15,27 Å; c 41,54 Åa b 90 ; g 120 ; V 8392 Å3C rM n6S 27/2Hexagonal R -3a b 23,32 Å; c 40,51 Åa b 90 ; g 120 ; V 19020 Å3Marvaud et al., Chemistry, 2003, 9, 1677 and 1692
electrons WANTED !How to manipulateelectrons between molecules ?Towards magnetsThe saga of high TC Prussian Blues Analogues
1704 2004 : 300th anniversary !Diesbach, draper in Berlin prepares a blue pigment « Prussian blue » said to be the first coordination compound
Classical Coordination Chemistry 3[Fe(CN)6]4-aq 4Fe3 aq{Fe4[Fe(CN)6]3}0 15H2O
CyanotypesEinstein a portrait, Cyanotypes by F. Villain, CIM2, UPMC
Magnetic Properties of Prussian BlueTC z J z : number of magneticneighbours J : coupling constantbetween nearestneighboursTC 5.6 KNéel, 1948
Ferromagnetic Prussian blue analogues TC z J JFerro 0OrthogonalityTC 5.6 K
Ferrimagnetic Prussian blue analogues TC z J JAntiferro 0Overlap TC 5.6 K
V4[Cr(CN)6]8/3.nH2OTC / K300d3VIIII(t2g )3d3quantumd4 3 F 9 AF 6 FMn [Cr(CN)6]36 F9 AFII100Room Temperature TCOn a rational basis !(t2g )39 AFCr200 d5d8NiIITiVFerlay et al. Nature, 1995CrMnFeCoMallah et al. Science 1993NiZCuZnGadet et al., J.Am. Chem. Soc. 1992
2[CrIII (CN)6 ]3- 3V aq 2 [V3[CrIII (CN6)]2]0macroA blue, transparent, low density magnet at room temperature
DevicesBased on Room temperature MagnetsPrussian blue analogues
Other deviceMagnetic Switch Or thermal probe CouplePermanentMagnetHotSample (MM)
Up to 2004 magnetic analogues used as macro devices and demonstrators
another demonstratorSample (MM)PermanentMagnetHeatermacro
another demonstratormacro
Chemists have managedto transformisolated single moleculesinto magnetsSingle MoleculeMagnets
What is namedSingle Molecule Magnet ? High SpinAnisotropic
High Spin Paramagnetic MoleculeH
Single Molecule MagnetH
Single Molecule MagnetifT TBlockingTowards information storage at the molecular level ?
Single molecule magnetszE0ThermalActivationyDS z2Anisotropy BarrierxTunneling- Szquantum-4 -2 0 2 4Sz Sz
[Mn12O12(CH3COO)16(H2O)4].2CH3COOH.4H20or Mn12Mn(III)S 2Mn(IV)S 3/2Ion OxydeCarboneS 8x2 -4x3/2 S 10From D.Gatteschi and R. Sessoli
Mn12 is a hard magnetMAGNETIZATION µ(B )RemnantMagnetisation20T 2.1K100-10-20Coercive Field-3-2-101MAGNETIC FIELD (T)23Bistability : inzero field themagnetisation canbe positive ornegativedepending of thestory of thesample
The dream Magnetic TipHigh Spin"down"High Spin"down" 10 nmquantumHSurfacemacro
Magnetic TipHigh Spin"down"High Spin"down" 10 nmquantumHSurfacemacro
The dream Magnetic TipHHSM «up»High Spin"down" 10 nmSurface information storage at the molecular level !
Nanosciences HHSM «up»High Spin"down" 10 nmSurface a challenge for chemists and friends
The possibilities are endless
Another popularnon scientific useof the word « magnetism »as attractive but less recommended
An interactionthrough spaceinvisible, incomprehensible Magnetism Magic !To be demystified
Levitating top
« This flask is equipped with magnets and induces in its centre an intense magneticfield which magnetizes the whole liquid.Keep in the magnetic flask, tap or mineral water or any other drink, from 15mns toseveral hours, for an optimum magnetization.Drink daily Magnetized Water : in preference, 1 cup when getting up, 1 or 2 in themorning and the afternoon and 1 cup at bedtime.As a matter of fact, the body and tyhe blood are composed at 70 and 80% ofwater, hence magnetized water, more lively, more energetizing due to its magneticproperties, carries its energy into the whole organism.Active research in hospitals, worldwide and mainly in China, havedemonstrated the beneficent effects of magnetized water.Some specialists foresee that .Magnetism will play an important rôle in the world of tomorrow.EURASIA TRADING COMPANY 5, place Anatole France 44 000 - Nantes45 6,40 de port
M. Noyori, Hanoi, october 2003To daythe chemist is ableto synthesizeany moleculeat will
High spinMolculesHigh TCMagnetsPhoto-MagnetsNEWMAGNETICOBJECTSSingle Chain MagnetsChiralMagnets
High spinMolculesHigh TCMagnetsPhoto-MagnetsBEAUTIFULOBJECTSSingle Chain MagnetsChiralMagnets
High spinMolculesM00.1101008121620Temperature /K24NEWPROPERTIES2.01hν2HHigh TCMagnetsPhoto-Magnets410001.51.0k!" / a. u.0.5Unpolarised light0.03456T/ K78Single Chain MagnetskChiralMagnetsId γd(w)k.M Id-
Earth needs care .Science for peace (Vincenzo Balzani)
Peace,PaixPace,PazPau, FriedePablo PicassoChild with a dove, 1901oil on canvas, 73x54 cmPrivate collectionon loan to National Gallery
spins molecular clusters nanoparticles micron particles permanent magnets Physics : Macroscopic Mesoscopic Nanoscopic-1 0 1-40 -20 0 20 40 M / M S µ 0H(mT) multi - domain nucleation, propagation and annihilation of domain walls-1 0 1-100 0 100 M / M S µ 0 H(mT) single - domain uniform rota
Introduction of Chemical Reaction Engineering Introduction about Chemical Engineering 0:31:15 0:31:09. Lecture 14 Lecture 15 Lecture 16 Lecture 17 Lecture 18 Lecture 19 Lecture 20 Lecture 21 Lecture 22 Lecture 23 Lecture 24 Lecture 25 Lecture 26 Lecture 27 Lecture 28 Lecture
they start nest-building soon after. The crows use many species of trees for nesting. In rural areas, Faragó (2002) found nests in seven tree species (Acer campestre, Carpinus betulus, Pyrus pyraster, Morus alba, Salix spp., Alnus spp. and Fraxinus spp. spp., Alnus. spp. and . Fraxinus. spp
Scientific Names of Organisms Mentioned in the Text 511 Common Names and Scientific Names of Organisms COMMON NAME SCIENTIFIC NAME Algae, green filamentous Oedogonium spp., Spirogyra spp., Ulothrix spp., Zygnema spp., and others Algae, medicinal Laminaria spp., Digenia spp., and ma
techniques have been used to feed a number of tick spe-cies of the family Ixodidae, including Rhipicephalus spp., Dermacentor spp., Amblyomma spp., Hyalomma spp., and Ixodes spp. using capillary tubes or membranes (briefly reviewed in [3]). Recently, Kröber and Guerin [1,4,5] established a method using a silicone membrane to engorge Ixodes .
SPP 2015 TPL-001-4 Short Circuit Planning Assessment for Selected UMZ Entities 2 y Date Author Change Description 12/23/2015 SPP staff Initial Draft 12/30/2015 SPP staff Final Draft . Southwest Power Pool, Inc. Table of Contents SPP 2015 TPL-001-4 Short Circuit Planning Assessment For Selected UMZ Entities 3 .
Southwest Power Pool, Inc. Revision History 2 2015 ITPNT Assessment Revision History Date Author Change Description 12/22/2014 SPP staff Draft 12/29/2014 SPP staff Approved by TWG 1/12/15 SPP staff Removed blank rows in Table 5.3 1/12/2015 SPP staff Added Final Reliability Assessment section 1/13/15 SPP staff Updated Table 5.4 with accurate costs per state
Tables LOT-2 Plants for Planting Manual 03/2021-66 301.38) 3-77 Table 3-17 Size and Age Restrictions for Dracaena spp. Entire (Whole) Plants Imported as Plants for Planting from Costa Rica 3-104 Table 3-18 Mangifera spp. Plants for Planting 3-133 Table 3-19 Poncirus spp. Seeds of Rutaceae Family 3-148 Table 3-20 Prunus spp. Plants (except Seeds) 3-159 Table 3-21 Prunus spp. Seeds Not .
Tables LOT-2 Cut Flowers and Greenery 04/2021-90 Table 3-8 Arecaceae (alt. Palmae) (palms) 3-9 Table 3-9 Capsicum spp. (pepper) Solanaceae 3-10 Table 3-10 Castanea spp. (chestnut), Fagaceae 3-11 Table 3-11 Chaenomeles spp. (flowering quince) Rosaceae 3-11 Table 3-12 Chrysanthemum spp. (mum) Asteraceae 3-12 Table 3-13 Coffea spp. (coffee) Rubiaceae
