[Pw_forum] how to convert crystal description

[sun jason]

dear all,

I have a silly question about structure description conversion,

for example, the relaxation result is like this:
-----------------------------------------------------------
     Final estimate of lattice vectors (input alat units)
   3.711193881  -0.138643395  -0.133568528
  -0.138262060   3.711099663   0.133354920
  -0.131446546   0.131591848   3.713501399
  final unit-cell volume =    343.8141 (a.u.)^3
  input alat =       1.8897 (a.u.)
-----------------------------------------------------------

then how to calculate a, b, c, and alpha, beta, gamma, if I want to 
describe the structure ?
I didn't find it in the solid state physics textbook, please give me some 
help.

Thank you very much!

Best regards,
===============================================
Jian SUN 
Physics Dept. of Nanjing University 
National Lab. of Solid State Microstructures 
22 Hankou Road, Gulou District 
Nanjing, Jiangsu Province 
210093 
China 
===============================================