awk '
FNR==1                  {gsub (/^.*\/|\..*$/, "", FILENAME)
                         print FILENAME 
                        }
/SCF Done:/             {print "Electronic Energy"
                         print $5
                        }
/Molecular mass/        {print "Molecular Weight (amu)"
                         print $(NF-1)
                        }
/Temperature/           {print "Values (If \"Interval\", give start and finish temp.)"
                         print $3
                        }
/Pressure/              {print "Pressure (in atm or bar - if given in atm, enter as a negative number. -1 is the G09 default)"
                         print ($NF=="Atm."?"-":"") $(NF-1)
                        }
/Multiplicity/          {print "Electronic degeneracy (multiplicity)"
                         print $NF "."
                        }
/Rotational.*ber/       {print "Rotational factor (symmetry factor)"
                         print $NF
                        }
/Frequencies/           {FC++;for (i=3; i<=5; i++) FR[FC,i]=$i}   
/Eigenvalues -- /       {gsub (/\.[0-9][0-9][0-9][0-9][0-9]/,"& ")
                         printf "Moments of Inertia (in amu x au2; none for Atom, 1 for Linear, 3 for General)\n%s\n%s\n%s\n",
                                $3, $4, $5
                        }
END                     {print "Vibrational Frequencies (first line: number; then freqs. in cm-1)"
                         print 3 * FC
                         for (i=3; i<=5; i++) for (j=1; j<=FC; j++) print FR[j,i]
                        }    
' /tmp/feco4_s.log.txt

feco4_s
Electronic degeneracy (multiplicity)
1.
Electronic Energy
-1715.82310939
Electronic degeneracy (multiplicity)
1.
Electronic Energy
-1715.82310939
Values (If "Interval", give start and finish temp.)
Kelvin.
Pressure (in atm or bar - if given in atm, enter as a negative number. -1 is the G09 default)
-1.00000
Molecular Weight (amu)
167.91460
Moments of Inertia (in amu x au2; none for Atom, 1 for Linear, 3 for General)
1284.73849
1536.05333
2170.19761
Rotational factor (symmetry factor)
2.
Vibrational Frequencies (first line: number; then freqs. in cm-1)
21
45.7886
96.4952
353.2741
427.8395
499.7992
640.4272
2062.0748
66.7894
96.9991
363.5129
430.9072
537.9941
640.7995
2062.6585
79.7836
335.4020
422.7705
448.4787
595.3209
2042.2981
2151.4066