procedure TForm1.Button3Click(Sender: TObject);
var
    sl : TStringList;
    xmlDoc : TXMLDocument;
    iNode,iNode2,iNode3 : IXMLNode;
    minhapasta:string;
    i:integer;
begin
minhapasta:=extractfilepath(application.exename);
xmlDoc := TXMLDocument.Create(nil);
try
xmlDoc.Active:=true;
xmlDoc.childNodes.Clear;
xmlDoc.Version:= '1.0';
xmlDoc.Encoding:= 'UTF-8';
      try
      iNode := xmlDoc.AddChild('arquivos');
          for i:=0 to listview1.Items.Count-1 do begin
          iNode2 := iNode.AddChild('arquivo');
          iNode2.Attributes['nome'] := listview1.Items.Item[i].Caption;
          iNode2.Attributes['crc32'] := listview1.Items.Item[i].SubItems.Strings[0];
        end;
      finally
          xmlDoc.SaveToFile(minhapasta+'arquivos.xml');
      end;
    finally
      xmlDoc := nil;
    end;
end;

<?xml version="1.0" encoding="UTF-8"?>
<arquivos><arquivo nome="xxx2.xxx" crc32="193E8327"/><arquivo nome="xxx.xxx" crc32="BBD12A50"/></arquivos>