received by the International Bureau on 16 January 2015 (16.01.2015)

What is claimed is:

1. A scintillator material comprising one of Formulas (I), (II I), (IV), (V), or

(VI):

'2(i-y)L'2yBX4 (II I);

A'_(1-y)L'_yB₂X₅ (IV);

A'V_y)L"_2yBX₄ (V); or

A"₍₁._y)L"_yB₂X₅ (VI);

wherein:

0.0001≤y<0.5;

A is one or more alkali metal;

A' is one or more of the group consisting of Li, K, Rb, and Cs;

A" is Na or a combination of Na and one or more additional alkali metal;

B is one or more alkali earth metal;

L is selected from the group consisting of Eu, Ce, Tb, Yb, and Pr; L' is selected from the group consisting of Tl, In, and Na;

L" is selected from the group consisting of Tl and In; and

X is one or more halide.

2. The scintillator material of claim 1 , wherein A or A' is selected from K, Rb, and Cs.

3. The scintillator material of claim 1 or claim 29, wherein B is selected from Sr and Ba.

4. The scintillator material of claim 1 , wherein X is selected from CI, Br, and I.

5. The scintillator material of claim 1 , wherein L is Eu and the scintillator material comprises A₂B(i__y)Eu_yX₄.

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6. The scintillator material of claim 1 , wherein 0.01

7. The scintillator material of claim 6, wherein 0.025≤y<0.05.

8. The scintillator material of claim 7, comprising A2Bo.95Euo.05X4.

9. The scintillator material of claim 7, wherein the scintillator material is selected from the group consisting of K₂Bal :Eu 5%; K₂BaBr₄:Eu 5%; Rb₂BaCI₄:Eu 5%; K₂SrBr₄:Eu 5%; and Rb₂BaCI₄:Eu 2.5%.

10. A radiation detector comprising a photon detector and a scintillation material, wherein the scintillation material comprises a scintillator material of claim 1 , claim 29, or claim 32.

11. The radiation detector of claim 10, wherein the detector is a medical diagnostic device, a device for oil exploration, or a device for container or baggage scanning.

12. A method of detecting gamma rays, X-rays, cosmic rays, and/or particles having an energy of 1 keV or greater, the method comprising using the radiation detector of claim 10.

13. A radiation detector comprising a photon detector and a scintillation material, wherein the scintillation material comprises one of Formulas (Γ), (III'), (IV), (V'), or (VI'):

A₂B_(1-Z)L_ZX₄ (I');

A _{z z}BX^III');

A'_(1-Z)L'_ZB₂X₅ (IV);

A"₂₍i_-z)L"_2zBX₄ (V); or

A"_(1-Z)L"_ZB₂X₅ (VI');

wherein:

0.0001≤z<1.0;

A is one or more alkali metal;

40 A' is one or more of the group consisting of Li, K, Rb, and Cs;

A" is Na or a combination of Na and one or more additional alkali metal;

B is one or more alkali earth metal;

L is selected from the group consisting of Eu, Ce, Tb, Yb, and Pr; L' is selected from the group consisting of Tl, In, and Na;

L" is selected from the group consisting of Tl and In; and

X is one or more halide.

14. The radiation detector of claim 13, wherein A or A' is selected from K, Rb, and Cs.

15. The radiation detector of claim 13 or claim 33, wherein B is selected from Sr and Ba.

16. The radiation detector of claim 13, wherein X is selected from CI, Br, and I.

17. The radiation detector of claim 13 wherein L is Eu and the scintillator material comprises A₂B(i-_Z)Eu_zX4.

18. The radiation detector of claim 13 or claim 33, wherein 0.01 <z<0.1.

19. The radiation detector of claim 13 or claim 33, wherein 0.025≤z<0.05.

20. The radiation detector of claim 13, wherein the scintillation material comprises A2Bo.95Euo.05X4-

21. The radiation detector of claim 13, wherein the scintillation material is selected from the group consisting of K₂Bal₄:Eu 5%; K₂BaBr₄:Eu 5%; Rb₂BaCI :Eu 5%; K₂SrBr₄:Eu 5%; and Rb₂BaCI₄:Eu 2.5%.

22. The radiation detector of claim 13, wherein z is 1.

23. The radiation detector of claim 22, wherein the scintillation material is K₂EuCI₄.

24. The radiation detector of claim 13 or claim 33, wherein the detector is a medical diagnostic device, a device for oil exploration, or a device for container or baggage scanning.

25. A method of detecting gamma rays, X-rays, cosmic rays, and/or particles having an energy of 1 keV or greater, the method comprising using the radiation detector of claim 13 or claim 33.

26. A method of preparing a scintillator material of claim 1 , claim 29, or claim 32, wherein the method comprises heating a mixture of raw materials above their respective melting temperatures.

27. The method of claim 26, wherein the method comprises:

(a) providing a mixture of raw materials, wherein the raw materials are provided in a stoichiometric ratio according to one of the formulas of claim 1 , claim 29, or claim 32;

(b) sealing said mixture in a sealed container;

(c) heating the mixture to about 20°C above the melting point of the raw material having the highest melting point for a period of time;

(d) cooling the mixture to about room temperature; and

(e) optionally repeating steps (c) and (d).

28. The method of claim 26, wherein the scintillator material is prepared in polycrystalline form.

29. A scintillator material comprising Formula (II):

AB₂₍₁__y)L_2yX₅ (II),

wherein:

0.0001<y≤0.5; A is one or more alkali metal, optionally wherein A is selected from K, Rb, and Cs;

B is one or more alkali earth metal;

L is selected from the group consisting of Eu, Ce, Tb, Yb, and Pr; and

X is one or more halide selected from F, CI, and Br, optionally wherein X is selected from CI and Br.

30. The scintillator material of claim 29, wherein L is Eu and the scintillator material comprises AB₂(i-y)Eu₂yX5.

31. The scintillator material of claim 29, wherein 0.01<y<0.1 ; optionally wherein 0.025≤y≤0.05; optionally wherein the scintillator material comprises AB2(o.975)Eu₂(o.o25) 5; optionally wherein the scintillator material is selected from the group consisting of RbSr₂CI₅:Eu 2.5%; KSr₂Br₅:Eu 2.5%; RbBa₂Br₅:Eu 2.5%; and RbSr₂Br₅:Eu 2.5%.

32. A scintillator material selected from the group consisting of KBa₂l₅:Eu 2.5%; CsSr₂l₅:Eu 2.5%; KSr₂l₅:Eu 4%; and KSr₂l₅:Eu 2.5%.

33. A radiation detector comprising a photon detector and a scintillation material, wherein the scintillation material comprises Formula (I I'):

AB_2(1-z)L_2zX₅ (ΙΓ),

wherein:

0.0001 <z<1.0;

A is one or more alkali metal, optionally selected from K, Rb, and Cs; B is one or more alkali earth metal;

L is selected from the group consisting of Eu, Ce, Tb, Yb, and Pr; and

X is one or more halide selected from the group F, CI, and Br, optionally selected from CI and Br.

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34. The radiation detector of claim 33, wherein L is Eu and the scintillator material comprises AB₂(i-z)Eu₂z 5.

35. The radiation detector of claim 33, wherein the scintillation material comprises AB₂(o.975)Eu₂(o.o25) 5, optionally wherein the scintillation material is selected from the group consisting of RbSr₂CI₅:Eu 2.5%; KSr₂Br₅:Eu 2.5%; RbBa₂Br₅:Eu 2.5%; and RbSr₂Br₅:Eu 2.5%.

36. The radiation detector of claim 33, wherein the scintillation material is RbEu₂CI₅.

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