The luminescence of Pr

3+

or Mn

2+

singly doped as well as Pr

3+

and Mn

2+

codoped SrB

4

O

7

powder microcrystalline samples were investigated using synchrotron radiation.The photon cascade emission originating from the

1

S

0

level was observed in the SrB

4

O

7

:Pr

3+

(0.1%

mol fraction)sample upon 206 nm excitation.There are desirable spectral overlaps in the region of 330

4

30 nm between the emission spectra of the SrB

4

O

7

:Pr

3+

sample and the excitation spectra of the SrB

4

O

7

:Mn

2+

sample monitoring the Mn

2+

luminescence at 640 nm.The wavelengths corresponding to transitions

1

S

0

1

I

6

3

P

2

1

0

(405 nm)and

1

S

0

1

D

2

(340 nm)of Pr

3+

coincide very well with those corresponding to transitions

6

A

1g

4

E

g

-

4

A

1g

(410 nm)and

6

A

1g

4

T

2g

(350 nm)of Mn

2+

respectively.These spectral overlaps are in favor of the energy transfer from Pr

3+

to Mn

2+

converting the first step photon from Pr

3+

:

1

S

0

in the unpractical ultraviolet or near-ultraviolet regions into the red Mn

2+

emission.A comparison of the room temperature emission spectra of the SrB

4

O

7

:Pr

3+

Mn

2+

sample with that of the SrB

4

O

7

:Pr

3+

sample revealed the existence of the proposed energy transfer between Pr

3+

and Mn

2+

.This conclusion about PrMn energy transfer was also supported by the evidences from the low temperature(10 K)spectra and decay curves of 405 nm emission from Pr

3+

singly doped and Pr

3+

Mn

2+

codoped samples.The efficiency of the energy transfer was estimated to be 43% by a simple equation based on the comparison of the emission spectra of the SrB

4

O

7

:Pr

3+

Mn

2+

sample with that of the SrB

4

O

7

:Pr

3+

sample

thus a 143% quantum efficiency was achieved

suggesting an promising VUV phosphor based on Pr

3+

and Mn

2+

combination.