JPS5943409B2 - Compound having hexagonal layered structure represented by YFeMnO↓4 and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel compound YFeMn04 having a hexagonal layered structure and a method for producing the same.

Conventionally, a compound having a hexagonal layered structure represented by YFe204 is known.

This compound is a compound in which divalent and trivalent iron ions are surrounded by five-coordinated oxygen ions, and Y has six-coordinated oxygen ions around them, as shown by Y3+Fe2+ Fe3+ 01-. Yes, it has magnetism. The present invention provides Fe2+ of the Y゜+Fe''+Fe゜+01- compound.
The object of the present invention is to provide a novel compound in which Mn2+ is replaced with Mn2+, and a method for producing the same.

In the compound represented by YF and eMn04 of the present invention, iron exists as Fe3+ ion, manganese exists as Mn2, and Y exists as trivalent ion, Y3+Fe3+Mn2
It can be expressed as +OH-.

This crystal has a hexagonal layered structure as shown in FIG. The largest circle indicates oxygen, the middle circle indicates Y, and the smallest black circle indicates Fe and Mn. Fe and Mn are entered randomly. The divalent ions of manganese and the trivalent ions of iron are surrounded by fifth-coordinated oxygen ions and occupy the same position crystallographically. Furthermore, Y has six-coordinated oxygen atoms around it.
Oxygen, an anion, has a dense structure. a, b and c indicate positions within the unit cell. Planar index (hkt), interplanar spacing (dX) (do is actual measurement, dc
(indicates calculated value), relative reflection intensity for X-rays (working%)
are shown in Table 1.

The space group is R″3m, the crystal habit is plate-like, and the lattice constant is as follows: a0=3.4964±0.00
02(X)c0=25.456±O, 003(X) 1st
dcCA〕IC%〕0038.51
88.485190064.2484.2432410
13.0083.00710 0101 2.946
2.946 100 0 9 2.8 30 2.8
29 431 04 2.735 2.734 921
0 5 2.6 03 2.6 03 601 0
7 2.3 27 8 2.3 27 0 810 lower 2
．． 19402.19351910101.94851.
9485521101.74811.74827410
13 1.6 44 2 1.6 44 3 101
1 6 1.6161 1.616 4 121014
1.5588 1.5588 31 This compound is useful as a magnetic material as well as a semiconductor material.

This compound can be produced by the following method.

Yttrium oxide (Y2O3), manganese oxide (M
nO) and iron oxide (Fe2O3) in a molar ratio of approximately 1:2:1, and heating the mixture at a temperature of 900°C or higher in a non-oxidizing atmosphere. Deheru. Commercially available yttrium oxides used in the present invention may be used as they are, but in order for the reaction between the oxides to proceed quickly, the smaller the particle size, the better.
In particular, it is preferably 10 μm or less.

Furthermore, when using it as a magnetic material, it is preferable to avoid contamination with impurities, so it is preferable that the raw material is of high purity and that it has been calcined in air at about 1000° C. for several hours. Manganese oxide of ordinary reagent grade level may be used. The particle size is preferably 10 Itm or less for the same reason as the yttrium oxide. Further, it is preferable to calcinate in a mixed gas of carbon dioxide and hydrogen (mixture ratio: 1:1 by volume) at 1000° C. for 1 day, and then rapidly cool it to 0° C., because the reaction speeds up. The iron oxide may be of special reagent grade. The particle size is 10μ as above.
It is preferable that it is below m. Moreover, it is preferable to calcined in air at 800° C. for one day. These raw materials may be used as they are, or alcohols, acetone, etc. may be thoroughly mixed. These mixing ratios are Y2O3, MnO, Fe2O
3 in a molar ratio of 1:2:1.

If this ratio is exceeded, the desired layered compound cannot be obtained. These mixtures are sealed in a quartz or glass container and heated under a non-oxidizing atmosphere.

Since manganese is in a divalent state, in an oxidizing atmosphere (for example, in the atmosphere), manganese will be oxidized and become trivalent, so it is necessary to be in a non-oxidizing atmosphere. The heating temperature may be 900°C or higher, and the heating time is 10 minutes or more, preferably 1 hour or more. There are no restrictions on the rate of temperature increase during heating. After the reaction is completed, it can be rapidly cooled to 0°C or rapidly drawn out into the atmosphere. The obtained YFeMnO4 compound had a black metallic luster and was found to have a crystalline structure by powder X-ray diffraction.

The valence of iron ions in the compound was determined by measuring the Mössbauer effect, and the valence of manganese ions was determined by gravimetric analysis, which measures the change in weight of the sample when it is heated in air. Example: Yttrium oxide (Y2O3) with a purity of 99.9% or more
Powder, manganese oxide (MnO) powder with a purity of 99.9% or more, and iron oxide (Fe2O3) with a purity of 99.9% or more
The powders were weighed at a molar ratio of 1:2:1, acetone was added in a mortar, and the mixture was thoroughly mixed to obtain a fine powder mixture with an average particle size of several μm.

The mixture was placed in a transparent quartz tube (with an inner diameter of 8 m0), the inside of the tube was lowered to a vacuum of 10-3 mmHg using a vacuum pump, maintained for about 1 hour, and then melt-sealed with a gas burner.
The sample was placed in a box-shaped siliconite furnace set at .degree. C. and heated for about 1 day, after which time the sample was removed and rapidly cooled to room temperature. What was obtained was a hexagonal layered compound of YFeMnO4. The properties of the crystals were as shown in Table 1.

[Brief explanation of the drawing]

The drawing is a diagram of a YFeMnO4 crystal of the present invention.

Claims (1)

[Claims] 1. A compound having a hexagonal layered structure represented by YFeMnO_4. 2 Yttrium oxide (Y_2O_3), manganese oxide (MnO) and iron oxide (Fe_2O_3) are mixed in a molar ratio of about 1:2:1, and this mixture is heated at 900°C or higher in a non-oxidizing atmosphere. A method for producing a compound having a hexagonal layered structure represented by YFeMnO_4, which comprises heating at a temperature.