opc.three is correct the PrimaryFilePath won't help much here, apologies.

However doing something like this

$server = "svr"

$sqlserver = new-object “Microsoft.SqlServer.Management.Smo.Server” $server

Invoke-Sqlcmd -Query "SELECT a.name ,

b.filename

FROM sys.sysdatabases a

INNER JOIN sys.sysaltfiles b ON a.dbid = b.dbid

WHERE fileid <> 2

ORDER BY name ;" -ServerInstance $sqlserver

should be closer to get the data file paths..just don't forget to add the snapins required.

And I also suggest using the Get-acl cmdlet.

edit: typo