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c. a. c. b. Crystal Structure MnDC- 3 and MnDC-4. c. a. b. c. MnDC-3 MnDC - 4. Edge share. Mn-O-Mn connectivity. Corner share. Mn. Mn. Mn. Mn. Mn. Mn. Mn. Mn. b. a. MnDC-3.
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c a c b Crystal Structure MnDC- 3 and MnDC-4 c a b c MnDC-3 MnDC - 4
Edge share Mn-O-Mn connectivity Corner share Mn Mn Mn Mn Mn Mn Mn Mn b a MnDC-3
Comparison of M2(H2O)[adipate]2 ( M = Mn, Fe) Mn2(H2O)[CO2(CH2)4CO2]2, Fe2(H2O)[CO2(CH2)4CO2]2 ,[adipate n=4 (even number) in M2(H2O)[CO2(CH2)4CO2]2(M= Mn and Fe)] Kim, Y.J.; Jung, D. Y. Inorg. Chem.2000, 39, 1470. Kim, Y.J.; Jung, D. Y. Bull. Korean Chem. Soc.2000, 21, 656. Kim, Y. J.; Lee, E. W.; Jung, D. Y. Chem. Mater.2001, 13, 2684.
Magnetism of MnDC-n (n=3 to 12) 100G 5K-300K SQUID [Wagner and Friedberg model] J = -1.81 ~ -2.04 g = 1.95 ~ 2.01 [Hiller model] J = -1.95 ~ -2.16 g = 1.95 ~ 2.02 (U=coth K-1/K,K=JS(S+1)/kT) (A=2.9167 B=208.04 C=15.543 and X=|J|/2kT)
Mn- Conformation of Terminal Carboxylate Groups Dicarboxylic acid Metal Dicarboxylate Glutaric (odd) Adipic (even) (odd) Mn- -Mn (even) -Mn
Thermal Analyses Obsd. Calcd. Obsd. Calcd(Mn2O3) Compound TH2O wt loss Torganic Residue wt. Loss MnDC-3 225-252 5.1 4.6 345-800 47.3 40.7 MnDC-4 228-248 4.3 4.3 306-800 39.9 37.9 MnDC-5 218-248 4.2 4.1 309-800 37.7 35.5 MnDC-6 220-236 4.1 3.8 302-800 34.0 33.4 MnDC-7 208-233 3.8 3.6 297-800 33.8 31.6 MnDC-8 195-229 3.5 3.4 275-800 32.7 29.9 MnDC-9 190-215 3.4 3.2 295-600 27.9 28.4 MnDC-10 160-200 3.2 3.1 260-600 26.8 27.0 MnDC-11 152-173 2.9 2.9 285-600 23.5 25.8 MnDC-12 145-165 2.8 2.8 275-600 24.2 24.7 Dehydration range N2 flow 10oC/min Mn2(H2O)[CO2(CH2)nCO2]2 Mn2[CO2(CH2)nCO2]2 Mn2O3 150-250 oC 600 oC
Conclusions • We opened a new series of Mn-dicarboxylate compounds, MnDC- n (n = 3 to 12), which contains tunable interlayer distance using various ,-dicarboxylic acids by hydrothermal synthesis. • The manganese-oxygen connectivity of both even and odd members of MnDC-n, are very similar and the resulting magnetic properties is predominantly antiferromagnetic ascribed to the Mn-O-Mn infinite chains. Acknowledgment We acknowledge financial support from the Electron Spin Science Center at POSTECH, which established as the excellent science research center by the KOSEF.