Review Article | Published:

Dynamic molecular crystals with switchable physical properties

Nature Chemistry volume 8, pages 644656 (2016) | Download Citation

Abstract

The development of molecular materials whose physical properties can be controlled by external stimuli — such as light, electric field, temperature, and pressure — has recently attracted much attention owing to their potential applications in molecular devices. There are a number of ways to alter the physical properties of crystalline materials. These include the modulation of the spin and redox states of the crystal's components, or the incorporation within the crystalline lattice of tunable molecules that exhibit stimuli-induced changes in their molecular structure. A switching behaviour can also be induced by changing the molecular orientation of the crystal's components, even in cases where the overall molecular structure is not affected. Controlling intermolecular interactions within a molecular material is also an effective tool to modulate its physical properties. This Review discusses recent advances in the development of such stimuli-responsive, switchable crystalline compounds — referred to here as dynamic molecular crystals — and suggests how different approaches can serve to prepare functional materials.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    (ed.) Spin-Crossover Materials: Properties and Applications (Wiley, 2013).

  2. 2.

    , , & Molecular spin crossover phenomenon: recent achievements and prospects. Chem. Soc. Rev. 40, 3313–3335 (2011).

  3. 3.

    , & Valence tautomerism in metal complexes: Stimulated and reversible intramolecular electron transfer between metal centers and organic ligands. Coord. Chem. Rev. 268, 23–40 (2014).

  4. 4.

    , & in Spin-Crossover Materials: Properties and Applications (ed. Halcrow, M. A.) 171–202 (Wiley, 2013).

  5. 5.

    , & Control of magnetic properties through external stimuli. Angew. Chem. Int. Ed. 46, 2152–2187 (2007).

  6. 6.

    , & Cooperation of hydrogen-bond and charge-transfer interactions in molecular complexes in the solid state. Bull. Chem. Soc. Jap. 86, 183–197 (2013).

  7. 7.

    & Development of conductive organic molecular assemblies: organic metals, superconductors, and exotic functional materials. Bull. Chem. Soc. Jap. 80, 1–137 (2007).

  8. 8.

    , , & Photochromism of diarylethene molecules and crystals: memories, switches, and actuators. Chem. Rev. 114, 12174–12277 (2014).

  9. 9.

    , & Photoinduced linkage isomers of transition-metal nitrosyl compounds and related complexes. Chem. Rev. 102, 861–883 (2002).

  10. 10.

    & Crystalline molecular machines: function, phase order, dimensionality, and composition. Chem. Soc. Rev. 41, 1892–1910 (2012).

  11. 11.

    , , & Thermally induced and photoinduced mechanical effects in molecular single crystals—a revival. CrystEngComm 16, 1850–1858 (2014).

  12. 12.

    & Ferroelectric metal–organic frameworks. Chem. Rev. 112, 1163–1195 (2012).

  13. 13.

    , , & in Topics in Current Chemistry Vol. 262, 99–132 (Springer, 2005).

  14. 14.

    Molecular Magnetism (VCH, 1993).

  15. 15.

    et al. Dynamical aspects of the photoinduced phase transition in spin-crossover complexes. Phys. Rev. Lett. 84, 3181–3184 (2000).

  16. 16.

    , & Thermal and optical switching of iron(ii) complexes. Angew. Chem. Int. Ed. Engl. 33, 2024–2054 (1994).

  17. 17.

    Calorimetric investigations of phase transitions occurring in molecule-based materials in which electrons are directly involved. Bull. Chem. Soc. Jap. 74, 2223–2253 (2001).

  18. 18.

    & Spin-transition polymers: from molecular materials toward memory devices. Science 279, 44–48 (1998).

  19. 19.

    et al. Synergetic spin crossover and fluorescence in one-dimensional hybrid complexes. Angew. Chem. Int. Ed. 54, 1574–1577 (2015).

  20. 20.

    et al. Photoswitching of the dielectric constant of the spin-crossover complex [Fe(L)(CN)2]·H2O. Angew. Chem. Int. Ed. 45, 1625–1629 (2006).

  21. 21.

    , , , & Light-induced excited spin state trapping in a transition-metal complex: the hexa-1-propyltetrazole-iron(ii) tetrafluoroborate spin-crossover system. Chem. Phys. Lett. 105, 1–4 (1984).

  22. 22.

    et al. First observation of light-induced excited spin state trapping for an iron(III) complex. J. Am. Chem. Soc. 122, 7126–7127 (2000).

  23. 23.

    , , , & Light-induced spin-crossover magnet. Nature Chem. 3, 564–569 (2011).

  24. 24.

    , & Pressure and temperature spin crossover sensors with optical detection. Sensors 12, 4479–4492 (2012).

  25. 25.

    , , & Pressure effect studies in molecular magnetism. Compt. Rend. Chimie 10, 21–36 (2007).

  26. 26.

    & Quantum tunneling of magnetization and related phenomena in molecular materials. Angew. Chem. Int. Ed. 42, 268–297 (2003).

  27. 27.

    et al. Pressure-induced Jahn–Teller switching in a Mn12 nanomagnet. Chem. Commun. 46, 1881–1883 (2010).

  28. 28.

    , , & Coordination assemblies of [Mn4] single-molecule magnets linked by photochromic ligands: photochemical control of the magnetic properties. J. Am. Chem. Soc. 131, 9823–9835 (2009).

  29. 29.

    et al. A light-induced phase exhibiting slow magnetic relaxation in a cyanide-bridged Fe4Co2 complex. Angew. Chem. Int. Ed. 51, 6361–6364 (2012).

  30. 30.

    et al. Tristability in a light-actuated single-molecule magnet. J. Am. Chem. Soc. 135, 15880–15884 (2013).

  31. 31.

    , , , & Photoinduced single-molecule magnet properties in a four-coordinate iron(II) spin crossover complex. J. Am. Chem. Soc. 135, 19083–19086 (2013).

  32. 32.

    et al. A light-induced spin crossover actuated single-chain magnet. Nature Commun. 4, 2826 (2013).

  33. 33.

    Molecular actuators driven by cooperative spin-state switching. Nature Commun. 4, 3607 (2013).

  34. 34.

    , , & [Fe(sal2-trien)][Ni(dmit)2]: towards switchable spin crossover molecular conductors. Chem. Commun. 69–70 (2005).

  35. 35.

    et al. Evidence of the chemical uniaxial strain effect on electrical conductivity in the spin-crossover conducting molecular system: [FeIII(qnal)2][Pd(dmit)2]5·acetone. J. Am. Chem. Soc. 130, 6688–6689 (2008).

  36. 36.

    , , , & Photomagnetic response in highly conductive iron(II) spin-crossover complexes with TCNQ radicals. Angew. Chem. Int. Ed. 54, 823–827 (2015).

  37. 37.

    A new spin on bistability. Nature Chem. 3, 189–191 (2011).

  38. 38.

    & Playing with organic radicals as building blocks for functional molecular materials. Chem. Soc. Rev. 41, 303–349 (2012).

  39. 39.

    & Room-temperature magnetic bistability in organic radical crystals. Science 286, 261–262 (1999).

  40. 40.

    et al. The key role of vibrational entropy in the phase transitions of dithiazolyl-based bistable magnetic materials. Nature Commun. 5, 4411 (2014).

  41. 41.

    et al. Hysteretic spin and charge delocalization in a phenalenyl-based molecular conductor. J. Am. Chem. Soc. 132, 17258–17264 (2010).

  42. 42.

    et al. Hysteretic spin crossover between a bisdithiazolyl radical and its hypervalent σ-dimer. J. Am. Chem. Soc. 132, 16212–16224 (2010).

  43. 43.

    , , , & Photoinduced solid state conversion of a radical σ-dimer to a π-radical pair. J. Am. Chem. Soc. 135, 15674–15677 (2013).

  44. 44.

    et al. Heat, pressure and light-induced interconversion of bisdithiazolyl radicals and dimers. J. Am. Chem. Soc. 136, 8050–8062 (2014).

  45. 45.

    , , & A functional nitroxide radical displaying unique thermochromism and magnetic phase transition. Angew. Chem. Int. Ed. 50, 10879–10883 (2011).

  46. 46.

    & Organic two-step spin-transition-like behavior in a linear S = 1 array: 3′-methylbiphenyl-3,5-diyl bis(tert-butylnitroxide) and related compounds. J. Am. Chem. Soc. 132, 9598–9599 (2010).

  47. 47.

    , , & Discovery of a neutral-to-ionic phase transition in organic materials. Phys. Rev. Lett. 46, 253–257 (1981).

  48. 48.

    , , & Chemical approach to neutral–ionic valence instability, quantum phase transition, and relaxor ferroelectricity in organic charge-transfer complexes. Chem. Phys. 325, 78–91 (2006).

  49. 49.

    et al. Thermodynamics of the neutral-to-ionic transition as condensation and crystallization of charge-transfer excitations. Phys. Rev. Lett. 79, 1690–1693 (1997).

  50. 50.

    et al. Anomalous nature of neutral-to-ionic phase transition in tetrathiafulvalene-chloranil. Phys. Rev. Lett. 47, 1747–1750 (1981).

  51. 51.

    et al. Electronic ferroelectricity in a molecular crystal with large polarization directing antiparallel to ionic displacement. Phys. Rev. Lett. 108, 237601 (2012).

  52. 52.

    , , & Ionic versus electronic ferroelectricity in donor-acceptor molecular sequences. Chem. Lett. 43, 26–35 (2014).

  53. 53.

    , , & Ultrafast modulation of polarization amplitude by terahertz fields in electronic-type organic ferroelectrics. Nature Commun. 4, 2586 (2013).

  54. 54.

    Electronic ferroelectricity in molecular organic crystals. J. Phys. Cond. Matter 26, 493201 (2014).

  55. 55.

    , & Ferroelectric Mott-Hubbard phase of organic (TMTTF)2X conductors. Phys. Rev. Lett. 86, 4080–4083 (2001).

  56. 56.

    et al. Strong optical nonlinearity and its ultrafast response associated with electron ferroelectricity in an organic conductor. J. Phys. Soc. Jap. 77, 074709 (2008).

  57. 57.

    et al. Charge transfer phase transition with reversed thermal hysteresis loop in the mixed-valence Fe9[W(CN)8]6·xMeOH cluster. Chem. Commun. 50, 3484–3487 (2014).

  58. 58.

    et al. Charge-transfer phase transition and ferromagnetism of iron mixed-valence complexes (n-CnH2n+1)4N[FeIIFeIII(dto)3] (n = 3–6; dto = C2O2S2). Eur. J. Inorg. Chem. 1198–1207 (2006).

  59. 59.

    , , , & Spin-entropy driven charge-transfer phase transition in iron mixed-valence system. Mater. Sci. Poland 21, 181–189 (2003).

  60. 60.

    et al. Reversible photoinduced magnetic properties in the heptanuclear complex [MoIV(CN)2(CN-CuL)6]8+: a photomagnetic high-spin molecule. Angew. Chem. Int. Ed. 43, 5468–5471 (2004).

  61. 61.

    , , , & Photomagnetism in clusters and extended molecule-based magnets. Inorg. Chem. 48, 3453–3466 (2009).

  62. 62.

    & Photomagnetism in cyano-bridged bimetal assemblies. Acc. Chem. Res. 45, 1749–1758 (2012).

  63. 63.

    Studies on charge distribution and valence tautomerism in transition metal complexes of catecholate and semiquinonate ligands. Coord. Chem. Rev. 216–217, 99–125 (2001).

  64. 64.

    et al. Genuine redox isomerism in a rare-earth-metal complex. Angew. Chem. Int. Ed. 51, 10584–10587 (2012).

  65. 65.

    Optically switchable molecular solids: photoinduced spin-crossover, photochromism, and photoinduced magnetization. Acc. Chem. Res. 36, 692–700 (2003).

  66. 66.

    et al. Temperature and light induced bistability in a Co3[Os(CN)6]2 6H2O prussian blue analog. J. Am. Chem. Soc. 132, 13123–13125 (2010).

  67. 67.

    , , & Photoinduced magnetization of a cobalt iron cyanide. Science 272, 704–705 (1996).

  68. 68.

    Molecular electronics emerges from molecular magnetism. Science 272, 698–699 (1996).

  69. 69.

    et al. Photoinduced ferrimagnetic systems in Prussian blue analogues CIxCo4[Fe(CN)6]y (CI = alkali cation). 1. Conditions to observe the phenomenon. J. Am. Chem. Soc. 122, 6648–6652 (2000).

  70. 70.

    , , & Photoinduced metal-to-metal charge transfer toward single-chain magnet. J. Am. Chem. Soc. 132, 8250–8251 (2010).

  71. 71.

    et al. Photoswitchable dynamic magnetic relaxation in a well-isolated {Fe2Co} double-zigzag chain. Angew. Chem. Int. Ed. 51, 5119–5123 (2012).

  72. 72.

    et al. Three-way switching in a cyanide-bridged CoFe chain. Nature Chem. 4, 921–926 (2012).

  73. 73.

    et al. Metal-to-metal electron transfer in Co/Fe Prussian blue molecular analogues: the ultimate miniaturization. J. Am. Chem. Soc. 136, 15461–15464 (2014).

  74. 74.

    et al. Reversible electron transfer in a linear {Fe2Co} trinuclear complex induced by thermal treatment and photoirraditaion. Angew. Chem. Int. Ed. 51, 4367–4370 (2012).

  75. 75.

    et al. Controlled intramolecular electron transfers in cyanide-bridged molecular squares by chemical modifications and external stimuli. J. Am. Chem. Soc. 133, 3592–3600 (2011).

  76. 76.

    et al. Thermochromic and photoresponsive cyanometalate Fe/Co squares: toward control of the electron transfer temperature. J. Am. Chem. Soc. 136, 16854–16864 (2014).

  77. 77.

    et al. A charge-transfer-induced spin transition in the discrete cyanide-bridged complex {[Co(tmphen)2]3[Fe(CN)6]2}. J. Am. Chem. Soc. 126, 6222–6223 (2004).

  78. 78.

    et al. Magnetic and optical bistability driven by thermally and photoinduced intramolecular electron transfer in a molecular cobalt-iron Prussian blue analogue. J. Am. Chem. Soc. 130, 252–258 (2008).

  79. 79.

    et al. An unprecedented charge transfer induced spin transition in an Fe–Os cluster. Angew. Chem. Int. Ed. 49, 1410–1413 (2010).

  80. 80.

    et al. Co-NC-W and Fe-NC-W electron-transfer channels for thermal bistability in trimetallic {Fe6Co3[W(CN)8]6} cyanido-bridged cluster. Angew. Chem. Int. Ed. 52, 896–900 (2013).

  81. 81.

    , , & Quinonoid metal complexes: toward molecular switches. Acc. Chem. Res. 37, 827–835 (2004).

  82. 82.

    , , , & Photo-induced valence tautomerism in Co complexes. Acc. Chem. Res. 40, 361–369 (2007).

  83. 83.

    , & Valence tautomeric transitions with thermal hysteresis around room temperature and photoinduced effects observed in a cobalt–tetraoxolene complex. J. Am. Chem. Soc. 128, 1790–1791 (2006).

  84. 84.

    et al. Soft-X-ray-induced redox isomerism in a cobalt dioxolene complex. Angew. Chem. Int. Ed. 49, 1954–1957 (2010).

  85. 85.

    & Photomechanical polymers. Synthesis and characterization of a polymeric pyrazine-bridged cobalt semiquinonate–catecholate complex. J. Am. Chem. Soc. 116, 2229–2230 (1994).

  86. 86.

    & Thermomechanical and photomechanical effects observed on crystals of a free-radical complex. Doklady Akademii Nauk Sssr 266, 1407–1410 (1982).

  87. 87.

    , & Proton-transfer-dependent reversible phase changes in the 4,4′-bipyridinium salt of squaric acid. Angew. Chem. Int. Ed. Engl. 33, 181–183 (1994).

  88. 88.

    S. et al. Temperature- and pressure-induced proton transfer in the 1:1 adduct formed between squaric acid and 4,4-bipyridine. J. Am. Chem. Soc. 131, 3884–3893 (2009).

  89. 89.

    , , , & Mechanochromism of piroxicam accompanied by intermolecular proton transfer probed by spectroscopic methods and solid-phase changes. J. Am. Chem. Soc. 127, 6641–6651 (2005).

  90. 90.

    & Organic ferroelectrics. Nature Mater. 7, 357–366 (2008).

  91. 91.

    , & A supramolecular ferroelectric realized by collective proton transfer. Angew. Chem. Int. Ed. 46, 3497–3501 (2007).

  92. 92.

    , & Ferroelectric order of parallel bistable hydrogen bonds. Phys. Rev. Lett. 89, 2155071–2155074 (2002).

  93. 93.

    et al. Above-room-temperature ferroelectricity in a single-component molecular crystal. Nature 463, 789–792 (2010).

  94. 94.

    et al. Above-room-temperature ferroelectricity and antiferroelectricity in benzimidazoles. Nature Commun. 3, 1308 (2012).

  95. 95.

    , , & Proton dynamics and room-temperature ferroelectricity in anilate salts with a proton sponge. J. Am. Chem. Soc. 130, 13382–13391 (2008).

  96. 96.

    et al. Proton-coupled electron transfer. Chem. Rev. 112, 4016–4093 (2012).

  97. 97.

    et al. Exploration of new cooperative proton-electron transfer (PET) systems. First example of extended conjugated quinhydrones: 1,5-dihalo-2,6-naphthoquinhydrones. J. Am. Chem. Soc. 113, 1862–1864 (1991).

  98. 98.

    , , , & Cooperative proton-electron transfer in a supramolecular structure of meso-1,2-bis-(4-dimethylaminophenyl)-1,2-ethanediol and bis(4-cyanobenzylidene)ethylenediamine. Adv. Mater. 8, 402–405 (1996).

  99. 99.

    et al. Hydrogen bond-promoted metallic state in a purely organic single-component conductor under pressure. Nature Commun. 4, 1344 (2013).

  100. 100.

    et al. Hydrogen-bond-dynamics-based switching of conductivity and magnetism: A phase transition caused by deuterium and electron transfer in a hydrogen-bonded purely organic conductor crystal. J. Am. Chem. Soc. 136, 12184–12192 (2014).

  101. 101.

    & Effect of pressure on photochromic furylfulgide. Eur. Phys. J. B 86, 218 (2013).

  102. 102.

    et al. New phases of C60 synthesized at high pressure. Science 264, 1570–1572 (1994).

  103. 103.

    , , & Inorganic–organic hybrid photochromic materials. Chem. Commun. 46, 361–376 (2010).

  104. 104.

    Diarylethenes for memories and switches. Chem. Rev. 100, 1685–1716 (2000).

  105. 105.

    , , , & Rapid and reversible shape changes of molecular crystals on photoirradiation. Nature 446, 778–781 (2007).

  106. 106.

    & Reversible photoinduced shape changes of crystalline organic nanorods. Adv. Mater. 19, 1276–1280 (2007).

  107. 107.

    , & Mechanical motion of azobenzene crystals upon photoirradiation. J. Am. Chem. Soc. 131, 6890–6891 (2009).

  108. 108.

    , & Reversible photoinduced twisting of molecular crystal microribbons. J. Am. Chem. Soc. 133, 12569–12575 (2011).

  109. 109.

    , & Photoinduced twisting of a photochromic diarylethene crystal. Angew. Chem. Int. Ed. 52, 9320–9322 (2013).

  110. 110.

    & Isomerization in photochromic ruthenium sulfoxide complexes. Eur. J. Inorg. Chem. 3895–3904 (2010).

  111. 111.

    & Necessary conditions for the photogeneration of nitrosyl linkage isomers. Phys. Chem. Chem. Phys. 11, 4391–4395 (2009).

  112. 112.

    et al. Direct observation of photochromic dynamics in the crystalline state of an organorhodium dithionite complex. Angew. Chem. Int. Ed. 45, 6473–6476 (2006).

  113. 113.

    et al. Photochromism of an organorhodium dithionite complex in the crystalline-state: Molecular motion of pentamethylcyclopentadienyl ligands coupled to atom rearrangement in a dithionite ligand. J. Am. Chem. Soc. 130, 17836–17845 (2008).

  114. 114.

    , , , & Spin switching effect in nickel nitroprusside: design of a molecular spin device based on spin exchange interaction. Chem. Mater. 9, 1092–1097 (1997).

  115. 115.

    et al. Thermally-induced phase transition of pseudorotaxane crystals: changes in conformation and interaction of the molecules and optical properties of the crystals. J. Am. Chem. Soc. 134, 17932–17944 (2012).

  116. 116.

    , , & A displacive-type metal crown ether ferroelectric compound: Ca(NO3)2(15-crown-5). Angew. Chem. Int. Ed. 53, 6724–6728 (2014).

  117. 117.

    et al. Bistability of magnetization without spin-transition in a high-spin cobalt(II) complex due to angular momentum quenching. J. Am. Chem. Soc. 131, 4560–4561 (2009).

  118. 118.

    L. et al. A new type of thermally induced spin transition associated with an equatorial ↔ axial conversion in a copper(II)–nitroxide cluster. J. Am. Chem. Soc. 117, 11247–11253 (1995).

  119. 119.

    et al. New spin-transition-like copper(II)-nitroxide species. Inorg. Chem. 46, 7545–7552 (2007).

  120. 120.

    et al. Light-induced excited spin state trapping in an exchange-coupled nitroxide-copper(II)-nitroxide cluster. Angew. Chem. Int. Ed. 47, 6897–6899 (2008).

  121. 121.

    et al. Photoswitching of a thermally unswitchable molecular magnet Cu(hfac)2Li−Pr evidenced by steady-state and time-resolved electron paramagnetic resonance. J. Am. Chem. Soc. 136, 10132–10138 (2014).

  122. 122.

    , , , & Supramolecular ferroelectrics. Nature Chem. 7, 281–294 (2015).

  123. 123.

    , , , & 13C NMR study of the C60 cluster in the solid state: molecular motion and carbon chemical shift anisotropy. J. Phys. Chem. 95, 9–10 (1991).

  124. 124.

    et al. Rotor–stator molecular crystals of fullerenes with cubane. Nature Mater. 4, 764–767 (2005).

  125. 125.

    , & Exceptionally large positive and negative anisotropic thermal expansion of an organic crystalline material. Nature Mater. 9, 36–39 (2010).

  126. 126.

    et al. Molecular motor-driven abrupt anisotropic shape change in a single crystal of a Ni complex. Nature Chem. 6, 1079–1083 (2014).

  127. 127.

    et al. 4-(cyanomethyl)anilinium perchlorate: a new displacive-type molecular ferroelectric. Phys. Rev. Lett. 107, 147601 (2011).

  128. 128.

    et al. 4-Methoxyanilinium perrhenate 18-Crown-6: a new ferroelectric with order originating in swinglike motion slowing down. Phys. Rev. Lett. 110, 257601 (2013).

  129. 129.

    et al. Ferroelectricity and polarity control in solid-state flip-flop supramolecular rotators. Nature Mater. 8, 342–347 (2009).

  130. 130.

    et al. Diisopropylammonium bromide is a high-temperature molecular ferroelectric crystal. Science 339, 425–428 (2013).

  131. 131.

    et al. Hydrogen-bonded displacive-type ferroelastic phase transition in a new entangled supramolecular compound. Cryst. Growth Des. 15, 457–464 (2015).

  132. 132.

    et al. Ferroelastic phase transition and switchable dielectric behavior associated with ordering of molecular motion in a perovskite-like architectured supramolecular cocrystal. J. Mater. Chem. C 1, 2561–2567 (2013).

  133. 133.

    Entropy diagnosis for phase transitions occurring in functional materials. Pure Appl. Chem. 77, 1331–1343 (2005).

  134. 134.

    et al. Towards the ultimate size limit of the memory effect in spin-crossover solids. Angew. Chem. Int. Ed. 47, 8236–8240 (2008).

  135. 135.

    & Natural strategies for photosynthetic light harvesting. Nature Chem. Biol. 10, 492–501 (2014).

  136. 136.

    et al. High hopes: can molecular electronics realise its potential? Chem. Soc. Rev. 41, 4827–4859 (2012).

Download references

Acknowledgements

Support from MEXT (Japan); KAKEN (No. 15H01018, 26104528, 25288029) is gratefully acknowledged.

Author information

Affiliations

  1. Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka Nishi-ku, Fukuoka, 819-0395, Japan

    • Osamu Sato

Authors

  1. Search for Osamu Sato in:

Competing interests

The author declares no competing financial interests.

Corresponding author

Correspondence to Osamu Sato.

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/nchem.2547

Further reading