Hi Barbara

I suppose you can use a scheduled script execution to generate an event.  

The execution can be scheduled or simply execute on 'Demand' by an admin or you can also set a 'conditional' script that will check if execute the script.

The event will be than used to trigger the email that will be sent to specific users or group of users.

Please refer to the following articles

Creating a Scheduled Job - ServiceNow Wiki

Events and Email Notification - ServiceNow Wiki

I hope this will help

Robo