Comparison of Enhancement Effect of DNA-Mediated Energy Transfer by Divalent Cations: Mg
2+
, Ca
2+
, Mn
2+
, Co
2+
, and Ni
2+
Jong-Moon Kim
1
, Myung Duk Jang
2
, JIN Biao
3,
*
, Yoon Jung Jang
4,
*