| 36 |  | * [1]  Meineke, et al., J. Comp. Chem. 26, 252-271 (2005). | 
| 37 |  | * [2]  Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006). | 
| 38 |  | * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008). | 
| 39 | < | * [4]  Vardeman & Gezelter, in progress (2009). | 
| 39 | > | * [4]  Kuang & Gezelter,  J. Chem. Phys. 133, 164101 (2010). | 
| 40 | > | * [5]  Vardeman, Stocker & Gezelter, J. Chem. Theory Comput. 7, 834 (2011). | 
| 41 |  | */ | 
| 42 |  |  | 
| 43 |  | #include <functional> | 
| 64 |  |  | 
| 65 |  |  | 
| 66 |  | template<typename T> | 
| 67 | < | struct logical_xor :public std::binary_function<T, T, bool> { | 
| 68 | < | RealType operator()(T x, T y) { return x ^ y; } | 
| 67 | > | struct logical_xor : public std::binary_function<T, T, bool> { | 
| 68 | > | T operator()(const T& x, const T& y) { return x ^ y; } | 
| 69 |  | }; | 
| 70 |  |  | 
| 71 |  | } |