Grigory
sargrigory@ya.ru
$CONTRL SCFTYP=RHF RUNTYP=OPTIMIZE $END
$SYSTEM MWORDS=60 $END
$BASIS GBASIS=N21 NGAUSS=3 $END
$DATA
O-O
C1
O 8 0.0 0.0 0.0
O 8 1.3 0.0 0.0
$END
it works just fine. But
$CONTRL SCFTYP=RHF RUNTYP=OPTIMIZE COORD=ZMT $END
$SYSTEM MWORDS=60 $END
$BASIS GBASIS=N21 NGAUSS=3 $END
$DATA
O-O
C1
O
O 1 1.3
$END
fails with "EXECUTION OF FIREFLY TERMINATED ABNORMALLY" in the output file. Similar examples with three atoms terminate normally.