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US3939252A
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Dilithium heptamolybdotetragadolinate
Assignee: WTA Inc
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Filing: 1974-03-06
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Granted: 1976-02-17
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Expires: 1994-03-06
Abstract
Abstract Dilithium heptamolybdotetragadolinate, Li 2 Gd 4 (MoO 4 ) 7 , is disclosed, along with three methods to prepare it. Two of the three methods are useful for growing single crystals of the material. The material exhibits electro-optic, paramagnetic and ferroelectric properties.
Inventors
- 👤 Raghvendra K. Pandey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:53
CPC Classifications
C; C30; C30B; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C01; C01G; C01G39/00; C01G39/006; C30B13/00; C30B15/00; C30B29/32; G; G02; G02F; G02F1/00; G02F1/0009; G02F1/0018; G02F1/0027; H; H01; H01G; H01G7/00; C01P; C01P2002/00; C01P2002/70; C01P2002/77; C01P2006/00; C01P2006/40
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
145 words
A method for the preparation of dilithium heptamolybdotetragadolinate represented by the formula Li 2 Gd 4 (MoO 4 ) 7 comprising the steps of: a. providing a charge of gadolinium oxide (Gd 2 O 3 ), molybdenum trioxide (MoO 3 ) and lithium molybdate (Li 2 MoO 4 ) in a respective mole ratio of 2:6:1; b. firing the charge at a temperature above about 800° centigrade and below about 1150° centigrade; c. maintaining the firing temperature for a time adequate to assure molecular homogeneity in the charge; d. increasing the temperature to about 1130° to 1250° centigrade; e. cooling from about 1130° to 1250° centigrate to about 400° to 600° centigrade over a period of about 100 to 200 hours; and f. cooling rapidly and without control to room temperature, and at least a portion of the dilithium heptamolybdotetragadolinate is in single crystal form.
Claim 2
Independent Claim
145 words
A method for the preparation of dilithium heptamolybdotetragadolinate represented by the formula Li 2 Gd 4 (MoO 4 ) 7 comprising the steps of: a. providing a charge of gadolinium oxide (Gd 2 O 3 ), molybdenum trioxide (MoO 3 ) and lithium molybdate (Li 2 MoO 4 ) in a respective mole ratio of 2:6:1; b. firing the charge at a temperature above about 800° centigrade and below about 1150° centigrade; c. maintaining the firing temperature for a time adequate to assure molecular homogeneity in the charge; d. increasing the temperature to about 1130° to 1250° centigrade; e. cooling from about 1130° to 1250° centigrate to about 400° to 600° centigrade over a period of about 100 to 200 hours; and f. cooling rapidly and without control to room temperature, and at least a portion of the dilithium heptamolybdotetragadolinate is in single crystal form.
Claim 3
Independent Claim
173 words
A method for the preparation of dilithium heptamolybdotetragadolinate represented by the formula Li 2 Gd 4 (MoO 4 ) 7 comprising the steps of: a. providing a charge of gadolinium oxide (Gd 2 O 3 ), molybdenum trioxide (MoO 3 ) and lithium molybdate (Li 2 MoO 4 ) in a respective mole ratio of 2:6:1; b. firing the charge at a temperature above about 800° centigrade and below about 1150° centigrade; c. maintaining the firing temperature for a time adequate to assure molecular homogeneity in the charge; d. increasing the temperature to about 1130° to 1250° centigrade; e. cooling from about 1130° to 1250° centigrade to about 850 to 500 degrees centigrade at a rate of about 0.5 to 5 centigrade degrees per hour; f. further cooling from about 850° to 500° centigrade to at least about 400° centigrade at a rate of about 100° centigrade per hour; and g. cooling rapidly and without control to room temperature, and at least a portion of the dilithium heptamolybdotetragadolinate is in single crystal form.
Claim 4
Independent Claim
173 words
A method for the preparation of dilithium heptamolybdotetragadolinate represented by the formula Li 2 Gd 4 (MoO 4 ) 7 comprising the steps of: a. providing a charge of gadolinium oxide (Gd 2 O 3 ), molybdenum trioxide (MoO 3 ) and lithium molybdate (Li 2 MoO 4 ) in a respective mole ratio of 2:6:1; b. firing the charge at a temperature above about 800° centigrade and below about 1150° centigrade; c. maintaining the firing temperature for a time adequate to assure molecular homogeneity in the charge; d. increasing the temperature to about 1130° to 1250° centigrade; e. cooling from about 1130° to 1250° centigrade to about 850 to 500 degrees centigrade at a rate of about 0.5 to 5 centigrade degrees per hour; f. further cooling from about 850° to 500° centigrade to at least about 400° centigrade at a rate of about 100° centigrade per hour; and g. cooling rapidly and without control to room temperature, and at least a portion of the dilithium heptamolybdotetragadolinate is in single crystal form.
Claim 5
Independent Claim
110 words
A method for the preparation of dilithium heptamolybdotetragadolinate represented by the formula Li 2 Gd 4 (MoO 4 ) 7 comprising the steps of: a. providing a charge of gadolinium oxide (Gd 2 O 3 ), molybdenum trioxide (MoO 3 ) and lithium molybdate (Li 2 MoO 4 ) in a respective mole ratio of 2:6:1; b. firing the charge at a temperature above about 800° centigrade and below about 1150° centigrade; c. maintaining the firing temperature for a time adequate to assure molecular homogeneity in the charge and; d. cooling the charge by means of the Czochralski vertical crystal pulling technique to yield a single crystal of dilithium heptamolybdotetragadolinate.
Claim 6
Independent Claim
110 words
A method for the preparation of dilithium heptamolybdotetragadolinate represented by the formula Li 2 Gd 4 (MoO 4 ) 7 comprising the steps of: a. providing a charge of gadolinium oxide (Gd 2 O 3 ), molybdenum trioxide (MoO 3 ) and lithium molybdate (Li 2 MoO 4 ) in a respective mole ratio of 2:6:1; b. firing the charge at a temperature above about 800° centigrade and below about 1150° centigrade; c. maintaining the firing temperature for a time adequate to assure molecular homogeneity in the charge and; d. cooling the charge by means of the Czochralski vertical crystal pulling technique to yield a single crystal of dilithium heptamolybdotetragadolinate.
References Cited (Backward Citations)
US3437432A
Cited
US3796585A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-02-16 | 1979-08-18 | 1980-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-16 | 1983-08-18 | 1984-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-16 | 1987-08-18 | 1988-02-17 | $7700.00 | Window Closed / Lapsed |