Setting the B0 recombination coefficient of each layer. If the material has n-layers you need to set B0 for each layer.
Format
$dirrecombine
B_1
B_2
B_3
...
B_n
Example
$dirrecombine
2.00e-11
2.00e-11
2.00e-11
2.00e-11
2.00e-11
The $dirrecombine setting for 1D-DDCC in GUI interface