Yuo could do something like this:

for (1..27) {
  open TEXT, ">cell_$_.txt" or die "Can't create cell_$_.txt: $!\n";
  printf TEXT "%14.11f  %14.11f  %14.11f  %14.11f  %14.11f  %14.11f\n"
+,$a, $b, $c, $alpha_deg, $beta_deg, $gamma_deg;
  close TEXT;
}
[download]

Of course you will have to set the variables inside the loop, but you propably are doing this already.

---- kurt