# MnO2의 전자상태 및 화학결합에 미치는 천이금속 첨가의 효과

• 이동윤 (한국전기연구원 재료응용연구단) ;
• 김봉서 (한국전기연구원 재료응용연구) ;
• 송재성 (한국전기연구원 재료응용연구) ;
• 김양수 (한국과학기술원 신소재공학과)
• Published : 2004.07.01

#### Abstract

The electronic state and chemical bonding of $\beta$-MnO$_2$ with transition metal dopants were theoretically investigated by DV-X$_{\alpha}$ (the discrete variational X$_{\alpha}$) method, which is a sort of the first principles molecular orbital method using the Hartree-Fock-Slater approximation. The calculations were performed with a $_Mn_{14}$ MO$_{56}$ )$^{-52}$ (M = transition metals) cluster model. The electron energy level, the density of states (DOS), the overlap population, the charge density distribution, and the net charges, were calculated. The energy level diagram of MnO$_2$ shows the different band structure and electron occupancy between the up spin states and down spin states. The dopant levels decrease between the conduction band and the valence band with the increase of the atomic number of dopants. The covalency of chemical bonding was shown to increase and ionicity decreased in increasing the atomic number of dopants. Calculated results were discussed on the basis of the interaction between transition metal 3d and oxygen 2p orbital. In conclusion it is expected that when the transition metals are added to MnO$_2$ the band gap decreases and the electronic conductivity increases with the increase of the atomic number of dopants. the atomic number of dopants.

#### References

1. J. power Sources v.79 synthesis, characterization and application of doped electrolytic manganede dioxdes W.Jantscher;L.Binder;D.A.Fiedler;R.Andreaus;K.Kordesch https://doi.org/10.1016/S0378-7753(98)00163-3
2. Electrochimica Acta v.24 The anodic characteristics of the massive β-MnO₂ doped with noble metals in sodium chlorode solution M.Morita;C.Iwakura;H.Tamura https://doi.org/10.1016/0013-4686(79)87045-0
3. Phys. Rew. B v.59 First-principles study on electrinic structures and phase stability of MnO and FeO under high pressure Z.Fang;I.V.solovyev;H.Sawaga https://doi.org/10.1103/PhysRevB.59.762
4. J. Quantum Chem. v.85 Inter. EHF theory of chemical reactions V. nature of manganede-oxygen bonds by hybrid density functional theory (DFT) and coupled-cluster (CC) methods H.Isobe;T.Soda;Y.Kitagawa;Y.Takano;T.Gawakami;Y.Yoshioka;K.Yamaguchi https://doi.org/10.1002/qua.1099
5. J. Am. Chem. Soc. v.121 Equilibrium geometry, stability, and magnetic properties of small MnO slusters S.K.Nayak;P.Jena https://doi.org/10.1021/ja981721p
6. J. Chem. Phys. v.114 Theoretical stydy of first-row transition metal oxide cations Y.Nakao;K,Hirao https://doi.org/10.1063/1.1362323
7. Chem. Phys. Lett. v.29 Origin of the unusal stability of MnO₄ G.L.Gutsev;B.K.Rao;P.Jena;X.Wang;L.Wang
8. J. Phys. Soc. Jpn. v.45 Application to metal clusters H.Adachi;M.Tsukada;C.Satoko https://doi.org/10.1143/JPSJ.45.875
9. Surf. Sci. v.58 Molecular cluster theory for dechemisorption of first raw atoms on nickel (100) surfaces D.E.Ellis;H,Adachi;F.W.Averill
10. 처음 배우는 전자 상태 계산 小和田善之;田中;中松博英;水野正降(저);김양수(역);신우석(역);강영석(역)
11. Australian J. Chem. v.46 A.A.Bolzan;C.Fong;B.J.Kennedy;C.J.Howard
12. Electronic Conduction in Oxides N,Tsuda;K.Nasu;A.Fujimori;K.Siratori
13. Electronic Conduction in Oxides N,Tsuda;K.Nasu;A.Fujimori;K.Siratori
14. Inorg. Chem. v.8 Crystal Chemistry of Metal Dioxides with Rutile-Related Strutures D.B.Rogers;R.D.Shannon;A.W.Sleight;L.Gillson https://doi.org/10.1021/ic50074a029