<a target="_blank" href="http://wpa.qq.com/msgrd?v=3&uin=1406838464&site=qq&menu=yes">
    发起会话
</a>

<a href="javascript:;" onclick="chatQQ()">QQ咨询</a>

function chatQQ(){
    //其中1234567指的是QQ号码
    window.location.href="mqqwpa://im/chat?chat_type=wpa&uin=1406838464&version=1&src_type=web&web_src=oicqzone.com";
}