TY - JOUR
T1 - Structure of lithium nitride and transition-metal-doped derivatives, Li3-x-yMxN (M = Ni, Cu)
T2 - A powder neutron diffraction study
AU - Gregory, Duncan H.
AU - O'Meara, Paul M.
AU - Gordon, Alexandra G.
AU - Hodges, Jason P.
AU - Short, Simine
AU - Jorgensen, James D.
PY - 2002/6/8
Y1 - 2002/6/8
N2 - Structures of lithium nitride (α-Li3N) and ternary nitridometalates Li3-x-yMxN (M = Ni, Cu) have been refined from time-of-flight powder neutron diffraction data using the Rietveld method. The parent binary nitride was synthesized by reaction of lithium metal with nitrogen using liquid sodium as a solvent. The ternary nitrides were prepared by reaction of Li3N with the respective transition metals under nitrogen. Refined data confirm the hexagonal structure previously reported by single-crystal X-ray diffraction for lithium nitride (P6/mmm, a = 3.6576(1) Å, c = 3.8735(1) Å, Z = 1) and show that the α-Li3N phase contains close to 3% Li vacancies at room temperature. The substituted nitridometalates, Li1.36Ni0.79N and Li2.21Cu0.40N, both form structures analogous to α-Li3N (P6/mmm, a = 3.7697(1) Å, c = 3.5270(1) A and a = 3.6791(1) Å, c = 3.7725(1) Å, respectively) in which the transition metal is disordered with Li between [Li2-yN] planes and Li vacancies are disordered within these planes. The nickel and copper nitrides contain 43% (y = 0.85) and 16% (y = 0.32) Li vacancies, respectively, within the [Li2N] planes and consequently contain transition metals predominantly in the +2 oxidation state.
AB - Structures of lithium nitride (α-Li3N) and ternary nitridometalates Li3-x-yMxN (M = Ni, Cu) have been refined from time-of-flight powder neutron diffraction data using the Rietveld method. The parent binary nitride was synthesized by reaction of lithium metal with nitrogen using liquid sodium as a solvent. The ternary nitrides were prepared by reaction of Li3N with the respective transition metals under nitrogen. Refined data confirm the hexagonal structure previously reported by single-crystal X-ray diffraction for lithium nitride (P6/mmm, a = 3.6576(1) Å, c = 3.8735(1) Å, Z = 1) and show that the α-Li3N phase contains close to 3% Li vacancies at room temperature. The substituted nitridometalates, Li1.36Ni0.79N and Li2.21Cu0.40N, both form structures analogous to α-Li3N (P6/mmm, a = 3.7697(1) Å, c = 3.5270(1) A and a = 3.6791(1) Å, c = 3.7725(1) Å, respectively) in which the transition metal is disordered with Li between [Li2-yN] planes and Li vacancies are disordered within these planes. The nickel and copper nitrides contain 43% (y = 0.85) and 16% (y = 0.32) Li vacancies, respectively, within the [Li2N] planes and consequently contain transition metals predominantly in the +2 oxidation state.
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U2 - 10.1021/cm010718t
DO - 10.1021/cm010718t
M3 - Article
AN - SCOPUS:0036266371
VL - 14
SP - 2063
EP - 2070
JO - Chemistry of Materials
JF - Chemistry of Materials
SN - 0897-4756
IS - 5
ER -