StepSize commands problem



 Please can some one give me any information how to use tha commands
 StepSize=N in gaussian, I was unable to make it working for my calculation
 it's always give me an error of syntax.
 are there any minimum limit or maximum limit?
 many thanks in advance, I will summarized to the list.
 Jaouad
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 /            Jaouad El-Bahraoui, Ph.D                               /
 /            University of Notre Dame                               /
 /            Dpto of Chemistry & Biochemistry                       /
 /            Notre Dame, Indiana 46556-5670                         /
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 /           Tel: (219)-631-4007                                     /
 /           Fax: (219)-631-6652                                     /
 /           Tel: (Home) (219)-243-8001                              /
 /           http://www.nd.edu/~jaouad                               /
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