Generate 512hash in c#

 public string Generatehash512(string text)
    {

        byte[] message = Encoding.UTF8.GetBytes(text);

        UnicodeEncoding UE = new UnicodeEncoding();
        byte[] hashValue;
        SHA512Managed hashString = new SHA512Managed();
        string hex = "";
        hashValue = hashString.ComputeHash(message);
        foreach (byte x in hashValue)
        {
            hex += String.Format("{0:x2}", x);
        }
        return hex;

    }