From VanBeek et al. Biophys J. (2007) 92, 4168-4178 
MASS
OA       16.00     0.465    same as gaff os and parm99 

BOND
CA-OA    372.40    1.373      same as gaff ca-os
CA- O    648.00    1.214      same as gaff c -o 

ANGLE
CA-CA-OA   69.800   119.200   same as gaff ca-ca-os
CA-CA-O    70.900   123.430   same as gaff ca-ca-o
CA-C -O    68.700   123.440   same as ca-c -o in gaff 
CA-C -O2   68.700   123.440   same as ca-c -o in gaff 
CA-OA-CA   63.600   118.960   same as GAFF ca-os-ca
CA-C -N    69.400   112.03    same as GAFF ca-c -n 

DIHE

IMPROPER 

NONBON
OA 1.6837 0.1700 OPLS ether e.g. same as gaff os