Untitled

Get-SPSite https://SitecollectionURL |
Select -ExpandProperty RootWeb |
Select -ExpandProperty Groups |
Where {$_.Name -EQ "SP Group Name"} |
Select -ExpandProperty Users |
Select Email

$smtp = "SMTP server addresss"
$to = "usersfromgroup@company.com"
$from = "sharepoint@company.com"
$subject = "This is a Test of HTML Email"
$body = "Dear Users"
$body += "We are testing HTML email"
$body += "<html> Click <a href=http://www.google.com>here</a>  to open google</html>"
send-MailMessage -SmtpServer $smtp -To $to -From $from -Subject $subject -Body $body -BodyAsHtml

param(
    $webUrl = "http://yoursite",
    $groupTitle = "your group"
)

clear-host

function Send-Mail($to){

    write-host "Sending email to $to..."
    $smtp = "SMTP server addresss"
    $from = "sharepoint@company.com"
    $subject = "This is a Test of HTML Email"
    $body = "Dear Users"
    $body += "We are testing HTML email"
    $body += "<html> Click <a href=http://www.google.com>here</a>  to open google</html>"
    send-MailMessage -SmtpServer $smtp -To $to -From $from -Subject $subject -Body $body -BodyAsHtml

}

Get-SPSite $webUrl | Select -ExpandProperty RootWeb |
    Select -ExpandProperty Groups |
    Where {$_.Name -eq $groupTitle} |
    Select -ExpandProperty Users |
    Select * | %{

        #do stuff here
        if($_.Email)
        {
            Send-Mail $_.Email
        }
}