Journal
INORGANIC CHEMISTRY
Volume 44, Issue 9, Pages 3194-3202Publisher
AMER CHEMICAL SOC
DOI: 10.1021/ic0484598
Keywords
-
Categories
Ask authors/readers for more resources
Tetraalkylammonium cations, (NR4)(+) (R = C3H7, CA, and C5H11), have been used as templates to form a new family of [M(dca)(3)](-) [M = Mn and Ni; dca = dicyanamide or N(CN)(2)(-)] salts. The tetrapropylammonium (TPrA) salts possess a perovskite-type anion structure. (TPrA)[Mn(dca)(3)] (1) crystallizes in the tetragonal space group P42(1)c, with a = 16.2945(8) angstrom, c = 17,4321(8) angstrom, and V = 4628.4(6) angstrom(3) at T = 298 K. At room temperature, (TPrA)[Ni(dca)(3)] (2) crystallizes in the orthorhombic space group Pnna, with a = 17.171(2) angstrom, b = 22.992(2) angstrom, c = 22.750(2) angstrom, and V = 8981(2) angstrom(3), but undergoes a first-order phase transition within the temperature range 150-220 K to the tetragonal space group P42(1)c, with a = 16.0985(7) angstrom, c = 17.0287(8) angstrom, and V = 4413.2(5) angstrom(3) at T = 160 K. At 110 K, 2 returns to the Pnna space group with a = 17.116(2) angstrom, b = 22.800(3) angstrom, c = 22.641(3) angstrom, and V = 8835(3) angstrom(3). The tetrabutylammonium (TBA) salts possess a triple rutile structure. (TBA)[Mn(dca)(3)] (3) crystallizes in the orthorhombic space group P2(1)2(1)2, with a = 16.0107(6) angstrom, b = 16.0114(6), c = 21.5577(8) angstrom, and V = 5526.4(5) angstrom(3). (TBA)[Ni(dca)(3)] (4) also crystallizes in the orthorhombic space group P2(1)2(1)2, with a = 15.6842(5) angstrom, b = 15.6841(6) angstrom, c = 21.1551(8) angstrom, and V = 5204.0(5) angstrom(3). The tetrapentylammonium (TPnA) salts crystallize with a LiSbO3 structure type, space group Pnna. Lattice parameters for (TPnA)[Mn(dca)(3)] (5) are a = 13.2236(6) angstrom, b = 11.6300(6) angstrom, c = 20.3176(9) angstrom, and V = 3124.6(4) angstrom(3), and for (TPnA)[Ni(dca)(3)] (6), a = 12.9380(4) angstrom, b = 11.6233(4) angstrom, c = 19.8038(7) angstrom, and V = 2978.1(2) angstrom(3). Long-range antiferromagnetic ordering has been observed in the manganese salts below 2.1 K, as indicated by alternating current susceptibility measurements. Magnetic susceptibility data for the nickel salts do not show evidence for long-range magnetic ordering but can be described using an S = 1 zero-field splitting model with the exchange Hamiltonian H= -J Sigma SiSj+1 + D Sigma(Si-j(z))(2) + g mu B-beta Sigma S-i, giving vertical bar D vertical bar/k(B) values that range between 1.98(1) K and 3.20(2) K.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available