Getting Error when changing from boost::array to std::array

I need to remove boost from this code. For some reason when calling the reference of the std::array now gives an error. Why?

Here are the arrays:

std::array<grid_dim, 3> gd; 
//boost::array<grid_dim, 3> gd;

Here is the struct:

struct grid_dim
{
    double begin;
    double end;
    std::size_t n; // number of intervals == number of sample points - 1
    grid_dim() : begin(0), end(0), n(0) {}
    double span() const { return end - begin; }
    bool enabled() const { return (n > 0); }
private:
    friend class boost::serialization::access;
    template<class Archive>
    void serialize(Archive& ar, const unsigned version) {
        ar & begin;
        ar & end;
        ar & n;
    }
};

Here is the call:

void main_procedure(...,const grid_dims& gd,...)

Here is the error:

Error   2   error C2664: 'main_procedure' : cannot convert parameter 8 from 'std::tr1::array<_Ty,_Size>' to 'const grid_dims &' C:\vina_code\vinaSingleThread\src\main\main.cpp 706 1   vinaSingleThread

Thank you for your time!