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Re: Can't freeze multiple bond lengths in GAMESS-US. Any ideas as to why?

Alexei Popov
alexei.a.popov@gmail.com

Hello,

try the following input:

\$CONTRL nzvar=1 \$END
\$ZMAT DLC=.T. auto=.t. NONVDW(1)=33,39, 4,30, 4,39, 27,20, 7,35,
26,16, 7,35, 25,20, 5,16, 16,28, 5,41 \$END
\$ZMAT IFREEZ(1)=1,5,41 fvalue(1)=2.00 \$END
\$ZMAT IFREEZ(4)=1,5,16 fvalue(2)=1.40 \$END
\$ZMAT IFREEZ(7)=1,16,28 fvalue(3)=1.40 \$END

Hope this helps
Alexei

On Wed Sep 23 '15 0:11am, Mr. Cho wrote
---------------------------------------
>I am trying to freeze the bond distance/length between atoms for (16,28), (5,16), and (5,41). When I try to use ifzmat and fvalue, only the constraint between atoms (16,28) is applied, while the other two are ignored. Could anyone tell me how to fix this?
>I have the following input file:

>\$BASIS GBASIS=PM3 \$END
>\$CONTRL SCFTYP=RHF RUNTYP=OPTIMIZE ICHARG=-1 MULT=1 ISPHER=1 \$END
>\$STATPT NSTEP=100 OPTTOL=0.0003 hssend=.t. \$END
>\$FORCE nvib=2 \$END
>\$ZMAT DLC=.T. auto=.t. NONVDW(1)=33,39, 4,30, 4,39, 27,20, 7,35,
>26,16, 7,35, 25,20, 5,16, 16,28, 5,41 \$END
>\$ZMAT DLC=.T. auto=.t. IFREEZ(1)=1,5,41 fvalue(1)=2.00 \$END
>\$ZMAT DLC=.T. auto=.t. IFREEZ(1)=1,5,16 fvalue(1)=1.40 \$END
>\$ZMAT DLC=.T. auto=.t. IFREEZ(1)=1,16,28 fvalue(1)=1.40 \$END
>\$CONTRL nzvar=0 \$END
>\$DATA
>Title
>C1
>C 6.0 33.53880 40.81519 80.3086
>.
>.
>.
>\$END

Sat Oct 3 '15 8:56pm