Your code is confusing to me and I am not sure what you are trying to do. However to answer part of the question, consider this:

#!usr/bin/perl
use warnings;
use strict;

#to print something verbatim, just use a single tick quote, ' versus "

my $head1='$contrl scftyp=rhf RUNTYP=energy coord=unique MULT=1 icharg
++=0 $end';
print $head1;

__END__

Prints:
$contrl scftyp=rhf RUNTYP=energy coord=unique MULT=1 icharg+=0 $end
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