RM1 (Recife Model 1)

J Comput Chem, 27 (2006) 1101-1111

RM1 is a re-parameterization of AM1 and offers somewhat improved performance.  The theoretical form is exactly the same as AM1 and offers no improvement in underlying methodology.  Careful re-optimization of the AM1 parameters using an improved dataset (both in quality and quantity) and better numerical methods resulted in a more accurate and precise method.

 

Property

No.

AM1

PM3

PM5

RM1

 DHf (kcal/mol)

1480

11.15

7.98

6.03

5.77

 Dipole Moments (m) 

127

0.37

0.38

0.50

0.34

 Ionization Potentials (eV) 

232

0.60

0.55

0.48

0.45

 Interatomic Distances ()

904

0.036

0.029

0.037

0.027