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1.Y. Wang, A. D. Price, and F. Caruso, “Nanoporous colloids: Building blocks for a new generation of structured materials,” J. Mater. Chem. 19, 64516464 (2009).
2.S. M. Adams, S. Campione, J. D. Caldwell, F. J Bezares, J. C. Culbertson, F. Capolino, and R. Ragan, “Non-lithographic SERS substrates: Tailoring surface chemistry for Au nanoparticle cluster assembly,” Small 8, 22392249 (2012).
3.W. T. Huck, “Effects of nanoconfinement on the morphology and reactivity of organic materials,” Chem. Commun. 2005, 41434148 .
4.N. Najmoddin, A. Beitollahi, E. Devlin, H. Kavas, S. M. Mohseni, J. Åkerman, D. Niarchos, H. Rezaie, M. Muhammed, and M. S. Toprak, “Magnetic properties of crystalline mesoporous Zn-substituted copper ferrite synthesized under nanoconfinement in silica matrix,” Microporous Mesoporous Mater. 190, 346355 (2014).
5.D. Carta, M. F. Casula, S. Bullita, A. Falqui, A. Casu, C. M. Carbonaro, and A. Corrias, “Direct sol-gel synthesis of doped cubic mesoporous SBA-16 monoliths,” Microporous Mesoporous Mater. 194, 157166 (2014).
6.I. B. Martini, I. M. Craig, W. C. Molenkamp, H. Miyata, S. H. Tolbert, and B. J. Schwartz, “Controlling optical gain in semiconducting polymers with nanoscale chain positioning and alignment,” Nat. Nanotechnol. 2, 647652 (2007).
7.D. Brühwiler, D. Calzaferri, T. Torres, J. H. Ramm, N. Gartmann, L. Dieu, I. Lopez-Duarte, and V. Martínez-Díaz, “Nanochannels for supramolecular organization of luminescent guests,” J. Mater. Chem. 19, 80408067 (2009).
8.X. Jiang, A. Ishizumi, N. Suzuki, M. Naito, and Y. Yamauchi, “Vertically-oriented conjugated polymer arrays in mesoporous alumina via simple drop-casting and appearance of anisotropic photoluminescence,” Chem. Commun. 48, 549551 (2011).
9.C. Aprile, A. Abad, H. García, and A. Corma, “Synthesis and catalytic activity of periodic mesoporous materials incorporating gold nanoparticles,” J. Mater. Chem. 15, 44084413 (2005).
10.A. Calvo, M. C. Fuertes, B. Yameen, F. J. Williams, O. Azzaroni, and G. Soler-Illia, “Nanochemistry in confined environments: Polyelectrolyte brush-assisted synthesis of gold nanoparticles inside ordered mesoporous thin films,” Langmuir 26, 55595567 (2010).
11.C. He, Y. Yu, C. Chen, L. Yue, N. Qiao, Q. Shen, J. Chen, and Z. Hao, “Facile preparation of 3D ordered mesoporous CuOx–CeO2 with notably enhanced efficiency for the low temperature oxidation of heteroatom-containing volatile organic compounds,” RSC Adv. 3, 1963919656 (2013).
12.P. F. Wang, H. X. Jin, M. Chen, D. F. Jin, B. Hong, H. L. Ge, J. Gong, X. L. Peng, H. Yang, Z. Y. Liu, and X. Q. Wang, “Microstructure and magnetic properties of highly ordered SBA-15 nanocomposites modified with and nanoparticles,” J. Nanomater. 2012, 17 (2012).
13.A. F. Gross, M. R. Diehl, K. C. Beverly, E. K. Richman, and S. H. Tolbert, “Controlling magnetic coupling between cobalt nanoparticles through nanoscale confinement in hexagonal mesoporous silica,” J. Phys. Chem. B 107, 54755482 (2003).
14.H. A. Lin, C. H. Liu, W. C. Huang, Z. C. Liou, M. W. Chu, H. C. Chen, J. F. Lee, and C. M. Yang, “Novel magnetically separable mesoporous Fe2O3 SBA-15 nanocomposite with fully open mesochannels for protein immobilization,” Chem. Mater. 20, 66176622 (2008).
15.X. Wang, M. Chen, L. Li, D. Jin, H. Jin, and H. Ge, “Magnetic properties of SBA-15 mesoporous nanocomposites with CoFe2O4 nanoparticles,” Mater. Lett. 64, 708710 (2010).
16.D. Weller and A. Moser, “Thermal effect limits in ultrahigh-density magnetic recording,” IEEE Trans. Magn. 35, 44234439 (1999).
17.D. Goll and S. Macke, “Thermal stability of ledge-type L1(0)-FePt/Fe exchange-spring nanocomposites for ultrahigh recording densities,” Appl. Phys. Lett. 93, 152512 (2008).
18.N. Weiss, T. Cren, M. Epple, S. Rusponi, G. Baudot, S. Rohart, A. Tejeda, V. Repain, S. Rousset, P. Ohresser, F. Scheurer, P. Bencok, and H. Brune, “Uniform magnetic properties for an ultrahigh-density lattice of noninteracting Co nanostructures,” Phys. Rev. Lett. 95, 157204 (2005).
19.R. P. Cowburn and M. E. Welland, “Room temperature magnetic quantum cellular automata,” Science 287, 14661468 (2000).
20.K. D. Sorge, A. Kashyap, R. Skomski, L. Yue, L. Gao, R. D. Kirby, S. H. Liou, and D. J. Sellmyer, “Interactions and switching behavior of anisotropic magnetic dots,” J. Appl. Phys. 95, 74147416 (2004).
21.D. L. Leslie-Pelecky and R. D. Rieke, “Magnetic properties of nanostructured materials,” Chem. Mater. 8, 17701783 (1996).
22.W. F. Brown, “Thermal fluctuations of a single-domain particle,” Phys. Rev. 130, 16771686 (1963).
23.H. C. Tong, C. Qian, L. Miloslavsky, S. Funada, X. Shi, F. Liu, and S. Dey, “Studies on antiferromagnetic/ferromagnetic interfaces,” J. Magn. Magn. Mater. 209, 5660 (2009).
24.N. A. Frey, S. Srinath, H. Srikanth, M. Varela, S. Pennycook, G. X. Miao, and A. Gupta, “Magnetic anisotropy in epitaxial CrO2 and CrO2/Cr2O3 bilayer thin films,” Phys. Rev. B 74, 024420 (2006).
25.B. Diouf, L. Gabillet, A. R. Fert, D. Hrabovsky, V. Prochazka, E. Snoeck, and J. F. Bobo, “Anisotropy, exchange bias, dipolar coupling and magnetoresistive response in NiO-Co-Al2O3-Co magnetic tunnel junctions,” J. Magn. Magn. Mater. 265, 204214 (2003).
26.D. Givord, V. Skumryev, and J. Nogues, “Exchange coupling mechanism for magnetization reversal and thermal stability of Co nanoparticles embedded in a CoO matrix,” J. Magn. Magn. Mater. 294, 111116 (2005).
27.X. R. Hu, P. W. Wu, and J. Yuan, “Exchange-coupled Fe3O4/L1(0)-FePt bilayer films by controlled oxidation of Fe/Pt multilayer,” Thin Solid Films 517, 26022605 (2009).
28.H. Oguchi, A. Zambano, M. Yu, J. Hattrick-Simpers, D. Banerjee, Y. Liu, Z. L. Wang, J. P. Liu, S. E. Lofland, D. Josell, and I. Takeuchi, “The effect of CoPt crystallinity and grain texturing on properties of exchange-coupled Fe/CoPt systems,” J. Appl. Phys. 105, 023912 (2009).
29.J. Li, Z. L. Wang, H. Zeng, S. H. Sun, and J. P. Liu, “Interface structures in FePt/Fe3Pt hard-soft exchange-coupled magnetic nanocomposites,” Appl. Phys. Lett. 82, 37433745 (2003).
30.H. Zeng, J. Li, J. P. Liu, Z. L. Wang, and S. H. Sun, “Exchange-coupled nanocomposite magnets by nanoparticle self-assembly,” Nature 420, 395398 (2002).
31.Z. Hao, S. Sun, T. S. Vedantam, J. P. Liu, Z. R. Dai, and Z. L. Wang, “Exchange-coupled FePt nanoparticle assembly,” Appl. Phys. Lett. 80, 25832585 (2002).
32.V. Franco, X. Batlle, A. Labarta, and K. O’Grady, “The nature of magnetic interactions in CoFe-Ag(Cu) granular thin films,” J. Phys. D: Appl. Phys. 33, 609613 (2000).
33.G. Bottoni, D. Candolfo, A. Cecchetti, and F. Masoli, “Interparticle interactions and magnetic parameters of iron powders for magnetic recording,” J. Magn. Magn. Mater. 116, 285290 (1992).
34.I. S. Jacobs and C. P. Bean, “An approach to elongated fine-particle magnets,” Phys. Rev. 100, 1060 (1955).
35.K. Ohshima, “Intergrain necking and the reversal of magnetization of fine, highly acicular ferromagnetic skeleton particles,” J. Mater. Sci. 36, 28152831 (2001).
36.X. C. Lu, S. H. Ge, L. X. Jiang, and X. W. Wang, “Chain of ellipsoids approach to the magnetic nanowire,” J. Appl. Phys. 97, 084304 (2005).
37.V. F. Puntes, “Colloidal nanocrystal shape and size control: The case of cobalt,” Science 291, 21152117 (2001).
38.J. Kim, C. Rong, J. P. Liu, and S. Sun, “Dispersible ferromagnetic FePt nanoparticles,” Adv. Mater. 21, 906909 (2009).
39.X. Wang, J. Zhuang, Q. Peng, and Y. Li, “A general strategy for nanocrystal synthesis,” Nature 437, 121124 (2005).
40.C. Wang, R. T. Lv, F. Y. Kang, J. L. Gu, X. C. Gui, and D. H. Wu, “Synthesis and application of iron-filled carbon nanotubes coated with FeCo alloy nanoparticles,” J. Magn. Magn. Mater. 321, 19241927 (2009).
41.N. R. Jana, Y. Chen, and X. Peng, “Size- and shape-controlled magnetic (Cr, Mn, Fe, Co, Ni) oxide nanocrystals via a simple and general approach,” Chem. Mater. 16, 39313935 (2004).
42.M. Gu, B. Yue, R. Bao, and H. He, “Template synthesis of magnetic one-dimensional nanostructured spinel MFe2O4 (M = Ni, Mg, Co),” Mater. Res. Bull. 44, 14221427 (2009).
43.S. Sun, “Recent advances in chemical synthesis, self-assembly, and applications of FePt nanoparticles,” Adv. Mater. 18, 393403 (2006).
44.L. E. M. Howard, H. L. Nguyen, S. R. Giblin, B. K. Tanner, I. Terry, A. K. Hughes, and J. S. O. Evans, “A synthetic route to size-controlled fcc and fct FePt nanoparticles,” J. Am. Chem. Soc. 127, 1014010141 (2005).
45.M. P. Pileni, “Self-assembly of inorganic nanocrystals in 3D supra crystals: Intrinsic properties,” Surf. Sci. 603, 14981505 (2009).
46.N. Sharma, G. H. Jaffari, S. I. Shah, and D. J. Pochan, “Orientation-dependent magnetic behavior in aligned nanoparticle arrays constructed by coaxial electrospinning,” Nanotechnology 21, 085707 (2010).
47.V. F. Puntes and K. M. Krishnan, “Synthesis, structural order and magnetic behavior of self-assembled epsilon-Co nanocrystal arrays,” IEEE Trans. Magn. 37, 22102212 (2001).
48.A. Wei, S. L. Tripp, J. Liu, T. Kasama, and R. E. Dunin-Borkowski, “Calixarene-stabilised cobalt nanoparticle rings: Self-assembly and collective magnetic properties,” Supramol. Chem. 21, 189195 (2009).
49.K. Xu, L. Qin, and J. R. Heath, “The crossover from two dimensions to one dimension in granular electronic materials,” Nat. Nanotechnol. 4, 368372 (2009).
50.Z. Tang and N. A. Kotov, “One-dimensional assemblies of nanoparticles: Preparation, properties, and promise,” Adv. Mater. 17, 951962 (2005).
51.F. X. Redl, K. S. Cho, C. B. Murray, and S. O’Brien, “Three-dimensional binary superlattices of magnetic nanocrystals and semiconductor quantum dots,” Nature 423, 968971 (2003).
52.M. P. Pileni, “Nanocrystal self-assemblies: Fabrication and collective properties,” J. Phys. Chem. B 105, 33583371 (2001).
53.L. T. Schelhas, R. A. Farrell, U. Halim, and S. H. Tolbert, “Directed self-assembly as a route to ferromagnetic and superparamagnetic nanoparticle arrays,” Adv. Func. Mater. (in press).
54.D. Y. Zhao, J. L. Feng, Q. S. Huo, N. Melosh, G. H. Fredrickson, B. F. Chmelka, and G. D. Stucky, “Triblock copolymer syntheses of mesoporous silica with periodic 50 to 300 angstrom pores,” Science 279, 548552 (1998).
55.G. S. Attard, J. C. Glyde, and C. G. Goltner, “Liquid-crystalline phases as templates for the synthesis of mesoporous silica,” Nature 378, 366368 (1995).
56.J. S. Beck, J. C. Vartuli, W. J. Roth, M. E. Leonowicz, C. T. Kresge, K. D. Schmitt, C. T. W. Chu, D. H. Olson, E. W. Sheppard, S. B. McCullen, J. B. Higgins, and J. L. Schlenker, “A new family of mesoporous molecular sieves prepared with liquid crystal templates,” J. Am. Chem. Soc. 114, 1083410843 (1992).
57.Q. S. Huo, D. I. Margolese, U. Ciesla, P. Y. Feng, T. E. Gier, P. Sieger, R. Leon, P. M. Petroff, F. Schuth, and G. D. Stucky, “Generalized synthesis of periodic surfactant inorganic composite-materials,” Nature 368, 317321 (1994).
58.Z. L. Yang, Y. F. Lu, and Z. Z. Yang, “Mesoporous materials: Tunable structure, morphology and composition,” Chem. Commun. 2009, 22702277 .
59.L. Cao, T. Man, and M. Kruk, “Synthesis of ultra-large-pore SBA-15 silica with two-dimensional hexagonal structure using triisopropylbenzene as micelle expander,” Chem. Mater. 21, 11441153 (2009).
60.M. Kruk, M. Jaroniec, C. H. Ko, and R. Ryoo, “Characterization of the porous structure of SBA-15,” Chem. Mater. 12, 19611968 (2000).
61.D. Zhao, Q. Huo, J. Feng, B. F. Chmelka, and G. D. Stucky, “Nonionic triblock and star diblock copolymer and oligomeric surfactant syntheses of highly ordered, hydrothermally stable, mesoporous silica structures,” J. Am. Chem. Soc. 120, 60246036 (1998).
62.S. Angloher and T. Bein, “Organic functionalisation of mesoporous silica,” Stud. Surf. Sci. Catal. 158, 20172026 (2005).
63.Y. H. Liu, H. P. Lin, and C. Y. Mou, “Direct method for surface silyl functionalization of mesoporous silica,” Langmuir 20, 32313239 (2004).
64.F. De Juan and E. Ruiz-Hitzky, “Selective functionalization of mesoporous silica,” Adv. Mater. 12, 430432 (2000).<430::AID-ADMA430>3.0.CO;2-3
65.C. T. Kresge, M. E. Leonowicz, W. J. Roth, J. C. Vartuli, and J. S. Beck, “Ordered mesoporous molecular sieves synthesized by a liquid-crystal template mechanism,” Nature 359, 710712 (1992).
66.E. Kockrick, P. Krawiec, W. Schnelle, D. Geiger, F. M. Schappacher, R. Pöttgen, and S. Kaskel, “Space-confined formation of FePt nanoparticles in ordered mesoporous silica SBA-15,” Adv. Mater. 19, 30213026 (2007).
67.L. Zhang, G. C. Papaefthymiou, and J. Y. Ying, “Synthesis and properties of γ-Fe2O3 nanoclusters within mesoporous aluminosilicate matrices,” J. Phys. Chem. B 105, 74147423 (2001).
68.M. Froba, R. Kohn, G. Bouffaud, O. Richard, and G. Van Tendeloo, “Fe2O3 nanoparticles within mesoporous MCM-48 silica: In situ formation and characterization,” Chem. Mater. 11, 28582865 (1999).
69.R. Köhn and M. Fröba, “Nanoparticles of 3d transition metal oxides in mesoporous MCM-48 silica host structures: Synthesis and characterization,” Catal. Today 68, 227236 (2001).
70.See supplementary material at for fully synthetic details, X-ray powder diffraction data on the mesoporous silica host, and on fcc and fct FePt nanocrystals, fully details on instrumentation used in this work and the 10 K and 298 K hysteresis curves used to determine these coercivity values.[Supplementary Material]
71.M. Chen, J. P. Liu, and S. H. Sun, “One-step synthesis of FePt nanoparticles with tunable size,” J. Am. Chem. Soc. 126, 83948395 (2004).
72.C. Kittel, “Theory of the structure of ferromagnetic domains in films and small particles,” Phys. Rev. 70, 965971 (1946).
73.L. Néel, “Théorie du traînage magnétique des ferromagnétiques en grains fins avec application aux terres,” Ann. Geophys. 5, 99136 (1949).
74.H. Zeng, R. Skomski, L. Menon, Y. Liu, S. Bandyopadhyay, and D. J. Sellmyer, “Structure and magnetic properties of ferromagnetic nanowires in self-assembled arrays,” Phys. Rev. B 65, 134426 (2002).
75.L. Sun, Y. Hao, C. L. Chien, and P. C. Searson, “Tuning the properties of magnetic nanowires,” IBM J. Res. Dev. 49, 79102 (2005).
76.Z. H. Cheng, J. H. Gao, Q. F. Zhan, H. Wei, and D. L. Sun, “Thermally activated magnetization reversal process of self-assembled Fe55Co45 nanowire arrays,” J. Magn. Magn. Mater. 305, 365371 (2006).
77.T. Fried, G. Shemer, and G. Markovich, “Ordered two-dimensional arrays of ferrite nanoparticles,” Adv. Mater. 13, 11581161 (2001).<1158::AID-ADMA1158>3.0.CO;2-6
78.P. Poddar, T. Telem-Shafir, T. Fried, and G. Markovich, “Dipolar interactions in two- and three-dimensional magnetic nanoparticle arrays,” Phys. Rev. B 66, 060403 (2002).
79.P. Y. Keng, I. Shim, B. D. Korth, J. F. Douglas, and J. Pyun, “Synthesis and self-assembly of polymer-coated ferromagnetic nanoparticles,” ACS Nano 1, 279292 (2007).
80.N. A. Spaldin, “Anisotropy,” in Magnetic Materials: Fundamentals and Device Applications (Cambridge University Press, 2003), Chap. 10, pp. 123131.
81.W. Wernsdorfer, E. B. Orozco, K. Hasselbach, A. Benoit, B. Barbara, N. Demoncy, A. Loiseau, H. Pascard, and D. Mailly, “Experimental evidence of the Néel-Brown model of magnetization reversal,” Phys. Rev. Lett. 78, 1791 (1997).
82.J. J. Benkoski, J. L. Breidenich, O. M. Uy, A. T. Hayes, R. M. Deacon, H. B. Land, J. M. Spicer, P. Y. Keng, and J. Pyun, “Dipolar organization and magnetic actuation of flagella-like nanoparticle assemblies,” J. Mater. Chem. 21, 73147325 (2011).
83.B. Kim, I. Shim, R. Sahoo, Z. Oskan, S. S. Saavedra, N. R. Armstrong, and J. Pyun, “Synthesis and colloidal polymerization of dipolar Au-Co core-shell nanoparticles into Au-Co3O4 nanowires,” J. Am. Chem. Soc. 132, 32343235 (2010).
84.E. V. Shevchenko, D. V. Talapin, N. A. Kotov, S. O’Brien, and C. B. Murray, “Structural diversity in binary nanoparticle superlattices,” Nature 439, 5559 (2006).
85.D. V. Talapin, E. V. Shevchenko, C. B. Murray, A. V. Titov, and P. Král, “Dipole-dipole interactions in nanoparticle superlattices,” Nano Lett. 7, 12131219 (2007).

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Mesoporous materials provide a unique host for controlling interactions between nanoscale guests. Here, we use polymer-templated mesoporous silicas to control magnetic dipole-dipole coupling between soft (superparamagnetic) face-centered-cubic and hard (ferromagnetic) face-centered-tetragonal FePt nanocrystals. We find that mixed soft-hard coupled FePt chains show enhanced magnetic coercivity, compared to single-component chains, while randomly associated nanocrystals show no change. A semi-quantitative analysis of temperature dependent magnetization data indicates that the free-energy barrier to spin flipping has both significant enthalpic and entropic components. Linear channels, thus, appear to be an effective way to organize magnetic nanocrystals with constructive dipolar coupling and tunable magnetic properties.


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