PowerShell Script to Export users List from SharePoint Group

Add - PSSnapin "Microsoft.SharePoint.PowerShell"
$siteUrl = "http://SharePointSite.com/"
$groupName = "GroupName Users"
$Output = @ ("Login")
$web = Get - SPWeb $siteUrl
$site = $web.Site
$rootWeb = $site.RootWeb
$UserList = $rootWeb.Lists["User Information List"]
$web.SiteGroups[$groupName].Users | %
{
    $user = $UserList.GetItemById($_.ID)
    if ($user - ne $null)
    {
        $JobTitle = $user["JobTitle"]
        $Department = $user["Department"]
    }
    $Output += ($_.UserLogin)
}
$rootWeb.Dispose()
$web.Dispose()
$site.Dispose()
$Output > "C:\MembersExport.csv"