we will explain how to calculate the matrix elements with TGVR basis functions. The typical matrix elements are also given in the appendix. In section 5, we will present and discuss the calculated scattering phase shifts in detail. Finally, summary and conclusions are given in section 6.

Microscopic $R$-matrix method {#sect.2}
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In the present study we calculate $d$+$d$ and $t$+$p$ (and $h$+$n$) elastic scattering phase shifts with the microscopic $R$-matrix method. Though the method is well documented in e.g. Refs. [@baye77; @kanada85; @desc10], we briefly explain it below in order to present definitions and equations needed in the subsequent sections. Since our interest is on low-energy scattering, we consider only two-body channels. A channel $\alpha$ is specified by the two nuclei (clusters) $a,
b$, their angular momenta, $I_a, I_b$, the channel spin $I$ that is a resultant of the coupling of $I_a$ and $I_b$, and the orbital angular momentum $\ell$ for the relative motion of $a$ and $b$. The wave function of channel $\alpha$ with the total angular momentum $J$, its projection $M$, and the parity $\pi$ takes the form $$\begin{aligned}
\Psi^{JM\pi}_{\alpha}=
{\cal A}
\left[\left[\Phi^{a}_{I_a}\Phi^{b}_{I_b}\right]_I  
\chi_{\alpha}
(\mbox{\boldmath$\rho$}_{\alpha})\right]_{JM},
\label{wf-ch1}\end{aligned}$$ where $\Phi^{a}_{I_a}$ and $\Phi^{b}_{I_b}$ are respectively antisymmetrized intrinsic wave functions of 