Using SQL Server 2012, what is the best data type to use for storing date time values.
DateTime or DateTime2?
The DateTime2 data type is most likely to be better!
It has greater range, better precision and a smaller storage. There is no particular reason in using the older DateTime data type.
Look here www.connectionstrings.com/sql-server-data-types-reference/ (scroll down to the table) for details regarding data types differences.