Send Email using SharePoint Rest API

SharePointSendEmail.js

var Email= function(){
// Email Either email groupname or email address
	var from = 'abc.yahoo.com',
		to = 'abc.yahoo.com',
		cc = 'abc.yahoo.com',  
		subject='My Email Subject'; 
		
	this.options = this.options || {};
	this.options['fromEmail'] = this.options['fromEmail'] || {};
	this.options['toEmail'] = this.options['toEmail'] || {};
	this.options['ccEmail'] = this.options['ccEmail'] || {};
	this.options['subject'] = this.options['subject'] || {};
	this.options['fromEmail'] = from;
	this.options['toEmail'] = to;
	this.options['ccEmail'] = cc;
	this.options['subject'] = subject;
	
	
}
function sendEmail(emailObj,body) {
		var that =emailObj;
        //Get the relative url of the site
        var ServiceUrl = ((_spPageContextInfo.webServerRelativeUrl==='/')?'/':_spPageContextInfo.webServerRelativeUrl);
        
        var siteurl = ServiceUrl;
        
        var urlTemplate = siteurl + "/_api/SP.Utilities.Utility.SendEmail";

        $.ajax({
            contentType: 'application/json',
            url: urlTemplate,
            type: "POST",
            data: JSON.stringify({
                'properties': {
                    '__metadata': {
                        'type': 'SP.Utilities.EmailProperties'
                    },
                    'From': that.options.fromEmail,
                    'To': {
                        'results': [that.options.toEmail]
                    },
					'CC': {
                        'results': [that.options.ccEmail]
                    },
                    'Body': body,
                    'Subject': that.options.subject
                }
            }),
            headers: {
                "Accept": "application/json;odata=verbose",
                "content-type": "application/json;odata=verbose",
                "X-RequestDigest": jQuery("#__REQUESTDIGEST").val()
            },
            success: function (data) {

            },
            error: function (err) {
				 // alert('Error in sending Email: ' + JSON.stringify(err));
				  alert('Error in sending Email', 1);
            }
        });
    }
	
var sendEmailObj = new Email();
var emailbody = 'hi this is email body';
sendEmail(sendEmailObj,emailbody);

are you sure this is working solution with external emails other the own domain?

"{"readyState":4,"responseText":"{"error":{"code":"-2130242040, Microsoft.SharePoint.SPException","message":{"lang":"en-US","value":"The e-mail message cannot be sent. Make sure the e-mail has a valid recipient."}}}","responseJSON":{"error":{"code":"-2130242040, Microsoft.SharePoint.SPException","message":{"lang":"en-US","value":"The e-mail message cannot be sent. Make sure the e-mail has a valid recipient."}}},"status":400,"statusText":"error"}"

SharePoint API doesn't allow posts to external emails. Must be an email of a SharePoint user email. This is as much as I know.

Can we add multiple email address dynamically for CC?