Complex sentence: AM1 was developed by Michael Dewar and co-workers, and published in 1985, as an attempt to improve the MNDO model by reducing the repulsion of atoms at close separation distances.
Split into simpler sentences: AM1 was developed by Michael Dewar and co-workers and published in 1985. AM1 is an attempt to improve the MNDO model by reducing the repulsion of atoms at close separation distances.