  Nodal line semimetals represent precursor states for various topological
phases, exhibiting intrinsic topological characteristics and intriguing
properties. These materials host rare and distinctive topological features,
which can give rise to exotic phenomena, thereby garnering significant
attention in both fundamental research and technological applications. In this
study, we conduct ab-initio calculations to explore the properties of SrCaX (X
= Bi, Sb, As, P), identifying these as multiple Dirac nodal line semimetals
protected by Z2 quantized Berry phases and manifesting multiple drum-head-like
surface states. The nodal lines in these compounds are situated at the M point
when kz = 0 and at the A point when kz = {\pi}. Notably, SrCaX family exhibits
a unique characteristic wherein they host both type II Dirac point and
topological nodal line semimetal within a single crystal structure, hence
providing an excellent platform for studying the interplay between different
topological properties. Additionally, in SrCaP topological Dirac semimetal,
Type II Dirac point and topological nodal line semimetal features coexist in a
single crystal. These special features in this series of materials make them
ideal candidates for further investigation by experimental means.
