10. Given that $\left\{ a _ { n } \right\}$ is an arithmetic sequence with non-zero common difference $d$. If $a _ { 2 } , a _ { 3 } , a _ { 7 }$ form a geometric sequence, and $2 a _ { 1 } + a _ { 2 } = 1$ , then $a _ { 1 } =$ $\_\_\_\_$ , $d =$ $\_\_\_\_$.\\