Since RSLogix doesn't use Tag Names, about the best you can do is export the Address/Description database, and then import that into Citect. You will have to come up with your own Tag Names in Citect.
RSLogix500 export: (with the source project open)
Tools, Database, ASCII Export, CSV tab. Check only the 'Addr/Symbol Desc.' box, and give it a destination file name with .CSV as the extension. Click OK. This will export all of the defined addresses, no matter if it is a Binary, Timer, etc. Data Type.
Citect Import:
You should already have the Citect Add-In for Excel installed, so you can edit any of the Citect .dbf files via Excel. If you haven't, contact Citect Tech Support.
Open the .CSV file you created previously with Excel. Adjust the import options as necessary to create a file with two columns, one with the PLC Addresses, one with the address Descriptions. Keep this worksheet open.
Use the Citect Add-In to open the Variable Tags database. Then copy and paste the addresses from the .CSV file into the 'ADDR' column and the descriptions from the .CSV file into the 'COMMENT' column. You will then create your own Tag Names for the 'NAME' column and assign each tag the Data Type and I/O Device in the 'TYPE' and 'UNIT' columns. Use the Save and ReIndex button in the Add-In to save this file. Before compiling, set the variable OID=1 in the citect.ini file so Citect will assign internal tag numbers to the new tags you added. Then compile. Hope this helps..!