public RangeDomainToken Create( 
   RangeDomainDescription rangeDomainDescription
)

// Create a range description with minimum value = 0 and maximum value = 1000
RangeDomainDescription rangeDomainDescriptionMinMax = new RangeDomainDescription("RangeDomain_0_1000",
  FieldType.Integer, 0, 1000)
{ Description = "Domain value ranges from 0 to 1000" };

SchemaBuilder schemaBuilder = new SchemaBuilder(geodatabase);

// Create  a range domain 
schemaBuilder.Create(rangeDomainDescriptionMinMax);
schemaBuilder.Build();