function mep_chemeddl(){
var space = "        ";
//jmolHtml("<b>Molecular Electrostatic Potential (MEP) Surface:</b>");
jmolBr();
var mepmenu  = "<input type=\"radio\" name=\"mepopt\" id=\"offradio\" onclick=\"setmepoptions('off')\" > No Potential Surface<br>";
    mepmenu += "<input type=\"radio\" name=\"mepopt\" id=\"mepradio\" onclick=\"setmepoptions('mep')\" checked> MEP on Isopotential Surface";
//    mepmenu += "&nbsp;&nbsp;<a href=\'javascript:alert(\"" + help_mepisopotential + "\")\'><img border=0 src='info_icon.png'></img></a><br>";
    mepmenu += "<br><input type=\"radio\" name=\"mepopt\" id=\"vdwradio\" onclick=\"setmepoptions('vdw')\"> MEP on Van der Waals Surface";
//    mepmenu += "&nbsp;&nbsp;<a href=\'javascript:alert(\"" + help_mepvdw + "\")\'><img border=0 src='info_icon.png'></img></a><br>";
    mepmenu += "<br>" + space + "<button onClick=\"setmepoptions('vol-')\">-</button> <button onClick=\"setmepoptions('vol+')\">+</button> Scale VdW volume";
    mepmenu += "<input type=\"text\" value=\"100\" id=\"vdwscale\" size=\"4\" readonly>%";
    mepmenu += "<br>";
    mepmenu += "<input type=\"radio\" name=\"mepopt\" id=\"planeradio\" onclick=\"setmepoptions('plane')\"> MEP on a plane<br>";
//    mepmenu += "&nbsp;&nbsp;<a href=\'javascript:alert(\"" + help_mepplane + "\")\'><img border=0 src='info_icon.png'></img></a><br>";
document.write(mepmenu);

var mepplane  = space + "<input type=\"text\" value=\"0 0 2 -1.0\" id=\"planeeq\" size=\"10\">";
    mepplane += "<button onClick=\"setmepoptions('plane')\">set plane equation</button><br>";
    mepplane += space + "<input type=\"radio\" align=\"bottom\" name=\"plane\" onClick=\"xyzplane('0 0 1 0')\" value=\"xy\">XY";
    mepplane +=         "<input type=\"radio\" align=\"bottom\" name=\"plane\" onClick=\"xyzplane('0 1 0 0')\" value=\"xz\">XZ";
    mepplane +=         "<input type=\"radio\" align=\"bottom\" name=\"plane\" onClick=\"xyzplane('1 0 0 0')\" value=\"yz\">YZ";
document.write(mepplane);
jmolBr();
jmolBr();
jmolBr();
// for mep: if the cutoff is with no sign it will show the surface with potential +/-value
// if a sign it is specified: + or - it will show only the blue(+) or the red(-) surface 
var mepbutton  = "min:<input type=\"text\" value='-0.1' id=\"negmepcutoff\" size=\"4\">";
    mepbutton += " max:<input type=\"text\" value='+0.1' id=\"posmepcutoff\" size=\"4\">";
    mepbutton += "<button onClick=\"setmepoptions('-')\">-</button>";
    mepbutton += "<button onClick=\"setmepoptions('+')\">+</button>";
//    mepbutton += "&nbsp;&nbsp;<a href=\'javascript:alert(\"" + help_mepcutoff + "\")\'><img border=0 src='info_icon.png'></img></a><br>";
    mepbutton += "<button onClick=\"setmepoptions('setcutoff')\">set this cutoff on surface</button>";
document.write(mepbutton);
}
function showpotential(button,show,hide,option,appletid){
        if (!document.getElementById)   
        return
        myvalue=document.getElementById(button).value;
        if (myvalue==show){
           document.getElementById(button).value=hide;
           //var cutoff = document.getElementById("mepcutoff").value;
	   setmepoptions('mep',appletid);
           document.getElementById('mepradio'+appletid).checked = true;
           //jmolScript("isosurface delete pos01 0.1 resolution 12 mep ;color isosurface translucent;");

           if (option.style.display=="block")
           option.style.display="none"
           else
           option.style.display="block"
        }
        if (myvalue==hide){
           document.getElementById(button).value=show;
           jmolScript("isosurface off;",appletid);
           document.getElementById('offradio'+appletid).checked = true;

           if (option.style.display=="block")
           option.style.display="none"
           else
           option.style.display="block"
        }
}
function showmo(button,show,hide,option,homo,appletid){
        if (!document.getElementById)   
        return
        myvalue=document.getElementById(button).value;
        if (myvalue==show){
           document.getElementById(button).value=hide;
	   setmooptions("homo",homo,appletid);
           document.getElementById('homo'+appletid).checked = true;

           if (option.style.display=="block")
           option.style.display="none"
           else
           option.style.display="block"
        }
        if (myvalue==hide){
           document.getElementById(button).value=show;
           jmolScript("mo off;",appletid);
           document.getElementById('offmo'+appletid).checked = true;

           if (option.style.display=="block")
           option.style.display="none"
           else
           option.style.display="block"
        }
}