Experimental determination of ionicity in MnO nanoparticles

Chemistry of Materials

Volumn 23, Issue 11, 2011, Pages 2956-2960

  Sun, Qi C ^a   Xu, Xiaoshan ^a,b   Baker, Sheila N ^b,c   Christianson, Andrew D ^b   Musfeldt, Janice L ^a  

^a UNIVERSITY OF TENNESSEE   (United States)

^b OAK RIDGE NATIONAL LABORATORY   (United States)

^c University of Missouri   (United States)

Author keywords

Born effective charge; finite length scale effect; ionicity; MnO; nanoparticles; phonon confinement

Indexed keywords

BORN EFFECTIVE CHARGE; FINITE LENGTH; IONICITY; MNO; PHONON CONFINEMENT;

CHEMICAL ANALYSIS; CHEMICAL BONDS; MATERIALS HANDLING EQUIPMENT; NANOPARTICLES; PHONONS; POLARIZATION;

MANGANESE OXIDE;

EID: 79958831916     PISSN: 08974756     EISSN: 15205002     Source Type: Journal    
DOI: 10.1021/cm200582t     Document Type: Article

References (45)

1. Orenstein, J.; Millis, A. J. Science 2000, 288, 468-474
2. Cheong, S.-W.; Mostovoy, M. Nat. Mater. 2007, 6, 13-20
3. Dresselhaus, M. S.; Chen, G.; Tang, M. Y.; Yang, R.; Lee, H.; Wang, D.; Ren, Z.; Fleurial, J.-P.; Gogna, P. Adv. Mater. 2007, 19, 1-12
4. Navrotsky, A.; Ma, C.; Lilova, K.; Birkner, N. Science 2010, 330, 199-201
5. Born, M.; Huang, K. Dynamical Theory of Crystal Lattices; Oxford University Press: London, 1954.
6. Resta, R.; Posternak, M.; Baldereschi, A. Phys. Rev. Lett. 1993, 70, 1010-1013
7. Homes, C. C.; Vogt, T.; Shapiro, S. M.; Wakimoto, S.; Ramirez, A. P. Science 2001, 293, 673-676
8. Dagotto, E. Nanoscale Phase Separation and Colossal Magneto-resistance: The Physics of Manganites and Related Compounds; Springer: Berlin, 2003.
9. Wyckoff, R. W. G. Crystal Structures; Interscience: New York, 1963.
10. Haywood, B. C.; Collins, M. F. J. Phys. C.: Solid State Phys. 1971, 4, 1299-1305
11. Rudolf, T.; Kant, Ch.; Mayr, F.; Loidl, A. Phys. Rev. B 2008, 77, 024421
12. Charges on the O centers are obviously equal and opposite.
13. Plendl, J. N.; Mansur, L. C.; Mitra, S. S.; Chang, I. F. Solid State Commun. 1969, 7, 109-111
14. Mochizuki, S. J. Phys.: Condens. Matter 1989, 1, 10351-10359
15. Savrasov, S. Y.; Kotliar, G. Phys. Rev. Lett. 2003, 90, 056401
16. Wdowik, U. D.; Legut, D. J. Phys.: Condens. Matter 2009, 21, 275402
17. Lee, G. H.; Huh, S. H.; Jeong, J. W.; Choi, B. J.; Kim, S. H.; Ri, H.-C. J. Am. Chem. Soc. 2002, 124, 12094-12095
18. Seo, W. S.; Jo, H. H.; Lee, K.; Kim, B.; Oh, S. J.; Park, J. T. Angew. Chem., Int. Ed. 2004, 43, 1115-1117
19. Ghosh, M.; Biswas, K.; Sundaresana, A.; Rao, C. N. R. J. Mater. Chem. 2006, 16, 106-111
20. Morales, M. A.; Skomski, R.; Fritz, S.; Shelburne, G.; Shield, J. E.; Yin, M.; O'Brien, S.; Leslie-Pelecky, D. L. Phys. Rev. B 2007, 75, 134423
21. Schladt, T. D.; Graf, T.; Tremel, W. Chem. Mater. 2009, 21, 3183-3190
22. Cao, J.; Vergara, L. I.; Musfeldt, J. L.; Litvinchuk, A. P.; Wang, Y. J.; Park, S.; Cheong, S. W. Phys. Rev. Lett. 2008, 100, 1772051
23. Kim, M.; Chen, X. M.; Joe, Y. I.; Fradkin, E.; Abbamonte, P.; Cooper, S. L. Phys. Rev. Lett. 2010, 104, 136402
24. Schleck, R.; Nahas, Y.; Lobo, R. P. S. M.; Varignon, J.; Lepetit, M. B.; Nelson, C. S.; Moreira, R. L. Phys. Rev. B 2010, 82, 054412
25. Jana, N. R.; Chen, Y.; Peng, X. Chem. Mater. 2004, 16, 3931-3935
26. X-ray diffraction experiments conducted at 300 K yield 4.439 and 4.445 Å for the nanoparticles and bulk (see Supporting Information), respectively, where as neutron diffraction experiments conducted at 300 K yield 4.4438 ± 20 Å and 4.4467 ± 3 Å. There is some systematic variation in these numbers (particularly for the nanoparticles), depending on the choice of background. We consider these systems to be essentially isostructural within our sensitivity.
27. 3, respectively. Therefore, pellet densities are ∼74% and ∼47% of the single crystal density, respectively; we correct for this difference in our analysis.
28. Homes, C. C.; Reedyk, M.; Cradles, D. A.; Timusk, T. Appl. Opt. 1993, 32, 2976-2983
29. -1 (lower right inset, Figure 3 b), characteristic of organic stretching modes. Thus, the measured nanoparticle reflectance spectrum contains information on both the MnO nanoparticles and the capping ligands.
30. Machefert, J. M.; Calvar, M. L.; Lenglet, M. Surf. Interface Anal. 1991, 17, 137-142
31. Here, we account for the small portion of the incident light that is reflected by the organic capping layer, the larger part of the incident light that will pass through the capping ligand and be reflected by the MnO, and the multiple internal reflections and transmissions that subsequently take place.
32. Wooten, F. Optical Properties of Solids; Academic Press: New York, 1972.
33. -2.
34. Sun, Q.-C.; Xu, X. S.; Vergara, L. I.; Rosentsveig, R.; Musfeldt, J. L. Phys. Rev. B 2009, 79, 205405
35. Xu, X. S.; Sun, Q.-C.; Rosentsveig, S.; Musfeldt, J. L. Phys. Rev. B 2009, 80, 014303
36. The bulk powder data has been corrected for surface scattering, and the nanoparticle data has been corrected for both surface scattering and the reflectance of the capping ligand.
37. Cowley, R. A. Rep. Prog. Phys. 1968, 31, 123-166
38. Eldridge, J. E.; Staal, P. R. Phys. Rev. B 1977, 16, 4608
39. And also capping ligand effects for the nanoparticles.
40. 4 and ±0.06 for the nanoparticles. The error bars of Z B*, α, and Z * are ±0.07, ±0.2, and ±0.03 for the single crystal, and ±0.05, ±0.3, and ±0.015 for the nanoparticles.
41. The depolarization factor is n = 1/3 for a cubic system.
42. Ashcroft, N. W.; Mermin, N. D. Solid State Physics; Thomson Learning: New York, 1976.
43. Masenelli, B.; Nicolas, D.; Melinon, P. Small 2008, 4, 1233-1239
44. -1 for bulk powder and nanoparticles, respectively.
45. Noguera, C. J. Phys.: Condens. Matter 2000, 12, R367-R410