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Preparation and X-Ray Investigation of Higher Uranium Nitrides.

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RN C O
-
+ HSPS(OCZH,)L
RNHCO-SPS(OC>Hs)z
n
+
RNC S
RNCS
Yield
R
(%)
liquid
70.5.- 7 I .5
liquid
65--66
liquid
56
45-46
liquid
69-70
76-77
80- 81
57
98.5
98
97
91
94.5
95
99
1.5135
68.5
73.5
31
-
69.5
61
44
54
73.5
100
1.5815
74
96
85.5
115-117
48
100
1
1
x
o(A)
70.5
1.45 121
10.700
[ I ] We did not obtain the N-phenyl derivative, but merely its
decomposition products, under the conditions described by A .
N . Pudorikand A . V . Kuznetsova, i.obSE. Chim. 25, 1369 (1955);
Huuben- Wevl: Methoden der Organischen Chemie. Thieme Verlag, Stuttgart 1955, Vol. 12/2, pp. 689, 823-824.
[2] J. P . Leber, Helv. chim. Acta, 49, 607 (1966).
Preparation and X-Ray Investigation of
Higher Uranium Nitrides
By Priv.-Doz. H. J. Berthold and C . Delliehausen
Institut fur Anorganische Chemie und Kernchemie der
Universitat Mainz (Germany)
Nitrides of uranium have been repeatedly studied in recent
years because of the importance of the mononitride as reactor fuel, yet there is no generally accepted opinion about
the composition of the various nitrides that can be obtained
from metallic uranium (produced from UH3) and nitrogen at
1 atm pressure.
Between 470 and 1000°C we have obtained the following
nitrides UN,:
X
I
1.74
I 510 I 580 I 700 I
770
1.68
1.64
1
1.76
I
I 1.67 I
I
I
830
1.63
1000
1.58
1.55
I
The proportions of nitrogen given are accurate within 1 %.
The time for nitrogen uptake was 62 hr at 470"C, 42 hr at
510 "C, and less than 30 min at 1000 "C. To prevent further
nitridation during cooling, the nitrides were either quenched
at the end of the reaction time or were cooled slowly under
helium.
726
10.675
1.62
I
I 1.67 I 1.71 I
I 10.662 I 10.650 I 10.645 I
1.64
10.665
[31
1.76
10.628
Rundle et al. [41 give lattice constants of 10.700 -1- 0.005 A for
UN1.50 and 10.601 f 0.005 8, (recalculated from kX units)
for UN1.75.
All the nitrides prepared by us with x 2 1.50 had the bodycentered cubic Mn2O3 structure. The continuous decrease in
intensity of the weak diffraction lines characteristic of this
structure type that occurred on transition from UN1.50 to
UN1.76 indicates a one-phase transition from the Mn2O3
structure to the face-centered cubic CaF2 structure of UNp,
as was assumed also by Rundle et al. [41. We assume that in
this process the nitrogen is taken into the UN1.50 lattice statistically. At UN1.76 the number of weak lines has been reduced to five [51.
We found no indication in the diffraction patterns for the
existence of discrete, stable phases such as have been demonstrated for the Pr0~.50-Pr02.0system [61.
Received: June 6th, 1966
[Z 261 lE]
German version: Angew. Chem. 78, 750 (1966)
_~__
[ I ] The values were obtained by extrapolation against cos2@
(camera diameter 57.3 mm, asymmetrical film position).
[2] The diffraction diagram for this nitride showed some weak
lines due to U N as well as the lines due to UNl.50.
[3] We obtained this nitride by treatment in an H2 stream for
5 hr at 500 "C.
[4] R . E. Rundle, N . C . Baenringer, A . S. Wilson, and R . A .
McDonald, J. Amer. chem. SOC.70, 99 (1948).
[5] For further details of the transition from the Mn2O3 type
to the CaFz type see G. Brauer and H . Gradinger, 2. anorg. allg.
Chem. 276, 209 (1954).
[6] Cf., for instance, B. C. Hyde, E. E. Garver, U.E. Kuntz, and
L . Eyring, J. physic. Chem. 69, 1667 (1965); J. M . Honig, A . F.
Clifford, and P . A . Faeth, Inorg. Chem. 2, 791 (1963); L. Evring
and N . C.Baenziger, J. appl. Physics 33, 428 (1962).
An Organometallic Compound with
Two-coordinatedFluorine Atoms
By Priv.-Doz. H. Schmidbaur and H. F. Klein
I-__
930 I
1
The lattice constants of the nitrides UN, obtained by direct
nitridation or by decompositon in an H2 stream decreased
linearly with increasing nitrogen content from 10.700 i
0.003 8, for UN1.50 to 10.628 & 0.008 A for UN1.76[11; the
wider limit of error is due to increase, at high glancing angle,
in the width of the lines and in the background with increasing nitrogen content.
10.680
Received: June 6th, 1966
[Z 260 IE]
German version: Angew. Chem. 75, 748 (1966)
470
*
1.55
112.8 g (0.604 mole) of 0,O'-diethyl hydrogen dithiophosphate is added dropwise to 60 g (0.604 mole) of n-butyl isocyanate with stirring, the temperature being kept at 20 to
25 OC by use of a cooling bath. At the end of the reaction the
S-butylcarbamoyl 0,O'-diethyl dithiophosphate (a strawcolored oil) is heated for 2 hours at 125-13OOC. Then, after
cooling, the solution is set aside for several hours, and the
upper layer is decanted, extracted with ice-water, dried with
anhydrous sodium sulfate, and distilled through a 90 cm
spinning-band column. Yield : 51 g of n-butyl isothiocyanate.
I
4 hr, UN1.58 after 6 hr, and UN1.45 after 20 hr. The nitrogen
content fell rapidly as far as UN1.62 (the composition of this
material corresponds approximately to a n equilibrium at
1 atm N2 pressure). Further decomposition as far as UN1.45
occurs more slowly and at an almost constant rate. UN1.74 is
decomposed to pure uranium mononitride within 1.5 hr in a n
H Z stream at 1200 "C. We found the lattice constant of U N
(NaCl type) to be a = 4.890 0.002 A, in agreement with
data in the literature.
1
I 1.58 1 1.60 I
I 10.692 I
1
I
Example of Synthesis:
Temp.('C)
Decomposition of the UNl.74 in a stream of hydrogen
(100 ml/min) at 800°C gave uN1.62 after 2 hr, UN1.60 after
(2)
(1)
Institut fur Anorganische Chemie der Universitat
Wurzburg (Germany)
An X-ray structure analysis[ll recently carried out on the
compound K[(C2H5)3AI-F-Al(C2H&]
confirmed the suggestion by Ziegler et al. [*I that a two-coordinated fluorine
atom occurs in the anions of this complex organoaluminum
fluoride. Surprisingly, however, it was found that the A1-F-A1
bridge is linear. This may be taken as evidence for spAngew. Chem. internat. Edit.
1 VoI. 5 (1966)
No. 8
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preparation, investigation, uranium, nitride, ray, higher
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