445
Ζ. Kristallogr. NCS 214 (1999) 445^46
© by Oldenbourg Wissenschaftsverlag, München
Crystal structure of dilithium (nitridolithiate/manganate(I)),
Li2[(Lii_xMnx)N], χ = 0.73
J. Klatyk1 and R. Kniep*·1·11
I
II
Max-Planek-Institut für Chemische Physik fester Stoffe, Pirnaer Landstr. 176, D-01257 Dresden, Germany
Technische Universität Darmstadt, Eduard-Zintl-Institut, Hochschulstraße 10, D-64289 Darmstadt, Germany
Received May 20, 1999, transferred to 2nd update of database ICSD in 1999, CSD-No. 409444
Discussion
Li2[(Lio.27Mno.73)N] is a member of a substitution series
Li2[(Lii-xMn'x)N] which crystallizes in the Li2[LiN] structure
type [2], This general type of substitution series is already known,
since the early work of Robert Juza et al. [3], who first reported
the existence of ternary compounds Li2[(Lii_/TEI.t)N] (TE = Co,
Ni, Cu) from X-ray powder investigations. Reinvestigations in
these systems [4, 5], based on single crystal data confirmed the
early observation, that the bond lenghts (Lii-jTE^-N decrease
with increasing χ parameter. In case of the title compound the
bond length (Lii- x MnJ-N (x = 0.73) within the infinite chains is
shortened from 193.8(1) pm in Li 2 [LiN] (x = 0) [2] to
191.4(2) pm. It is interesting to note that the decrease of the bond
lengths of (Lii-jMnJ-N with increasing χ parameter is much
smaller compared with the isotypic phases Li2[(Lii- x TE' x )N]
(TE1 = Fe [6], Co, Ni, Cu [3-5]).
Table 1. Data collection and handling.
Abstract
Li2.27Mno.73N, hexagonal, P6/mmm (No. 191), a = 3.7263(4) Ä,
c = 3.8281(4) Ä, V= 46.0 Ä3, Z = 1, R&(F) = 0.025,
wR(F2)
= 0.063, Τ = 293 Κ.
Source of material
Single crystals of I^IXLii-jMnViN] (x = 0.73) were obtained by
thermal treatment of mixtures of Li7[MnN4] [ 1 ] and Li with molar
ratios of 1:1 in Ta crucibles under Ar (1 atm). The mixtures were
first heated to 523 Κ (1.3 K/min, 12h) and then heated to 1173K
(3 K/min). After reaching the maximum temperature the reaction
products were cooled down (3 K/min) to ambient temperature.
Crystal:
Wavelength:
μ:
Diffractometer, scan mode:
28max:
N(hkl)measured, N(hkl)miquc:
C r i t e r i o n f o r / 0 bs, N(hkl)gt:
N(param),er,ned'·
Programs:
brass plate, size 0.2 χ 0.2 χ 0.4 mm
Mo Ka radiation (0.71070 A)
48.43 cm"1
Siemens P4, ω/2θ
59.6°
257,44
/obs > 2 cf/obs), 44
8
SHELXL-97 [7], DIAMOND [8]
Table 2. Atomic coordinates and displacement parameters (in Ä 2 ).
Atom
Site
Mn
Li(l)
Ν
Li(2)
lb
lb
la
2c
X
0.73(2) 0
0.27
0
0
1/3
y
ζ
t/ll
U22
U33
Un
Un
Un
0
0
0
2/3
1/2
1/2
0
0
0.0305(6)
0.0305
0.019(2)
0.047(4)
Un
Uu
U\i
0.0081(6)
0.0081
0.009(2)
0.040(6)
0.0153(3)
0.0153
0.0094(8)
0.024(2)
0
0
0
0
0
0
0
0
Uu
* Correspondence author (e-mail: [email protected])
Unauthenticated
Download Date | 6/19/17 6:39 AM
446
Acknowledgment.
We thank the Deutsche Forschungsgemeinschaft
(Schwerpunktprogramm "Reaktivität von Festkörpern") for supporting this
work.
References
1. Juza, R.; Anschütz, E.; Puff, H.: Die Struktur von L17VN4 und Li7MnN4.
Angew. Chem. 71(1959) 161.
2. Rabenau, Α.; Schulz, Η.: Re-Evaluation of the Lithium Nitride Structure.
J. Less-Common Met. 50 (1976) 155-159.
3. Sachsze, W., Juza, R.: Über Mischkristalle der Zusammensetzung
(Li,Co)3N, (Li,Ni)3N und (Li,Cu)3N. Z. Anorg. Allg. Chem. 259 (1948)
278-290.
Dilithium (nitridolithiate/manganate(I))
4. Gudat, Α.: Ternäre und quaternäre Nitride und Nitridometallate in
Systemen Lithium-Erdalkalimetall-Übergangsmetall-Stickstoff. Dissertation, Universität Düsseldorf, Germany 1990.
5. Höhn, P.: Temäre und quaternäre Nitridometallate: Verbindungen in den
Systemen Lithium-Erdalkalimetall-Übergangsmetall-Stickstoff.
(Übergangsmetall = Ta, Mo, W, Fe, Co). Dissertation, TH Darmstadt,
Germany 1993.
6. Klatyk, J.; Kniep, R.: Crystal structure of dilithium (nitridolithiate/ferrate), Li 2 [Lii- I Fe i )N], λ = 0.63. Ζ. Kristallogr. NCS 214 (1999)
447-448.
7. Sheldrick, G. M.: SHELXL-97, a program for refining crystal structures.
University of Göttingen, Germany 1997.
8. Brandenburg, K.: DIAMOND (Version 2.1a). Crystal Impact GbR,
Germany 1996-1999.
Unauthenticated
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