This paper is part of a series that focuses on investigating galaxy formation and evolution in small–scale systems of galaxies ( SSSGs ) in low–density environments .
We present results from a study of the NGC 4756 group which is dominated by the elliptical galaxy NGC 5746 .
The characteristics of the group are investigated through ( a ) the detailed investigation of the morphological , photometric and spectroscopic properties of nine galaxies among the dominant members of the group ( b ) the determination of the photometric parameters of the faint galaxy population in an area of 34′ \times 34′ centered on NGC 4756 and ( c ) an analysis of the X-ray emission in the area based upon archival data .

The nine member galaxies are located in the core part of the NGC 4756 group ( a strip diameter \approx 300 kpc in diameter , H _ { 0 } = 70 km s ^ { -1 } Mpc ^ { -1 } ) which has a very loose configuration .
The central part of the NGC 4756 group contains a significant fraction of early–type galaxies .
Three new group members with previously unknown systemic velocities are identified , one of which is a dE .
At about 7.5′ SW of NGC 4756 a sub–structure of the group is detected , including IC 829 , MCG –2–33–35 , MCG –2–33–36 and MCG –2–33–38 , which meets the Hickson criteria for being a compact group .
Most of the galaxies in this sub-structure show interaction signatures .
We do not detect apparent fine structure and signatures of recent interaction events in the early–type galaxy population , with the exception of a strong dust lane in the elliptical MCG –2–33–38 .
This galaxy displays however signatures of nuclear activity .
Strong [ O III ] , [ N II ] and [ S II ] line emission , combined with comparatively weak , but broad H \alpha emission suggest an intermediate Seyfert type classification .

Although the area is heavily contaminated by the background cluster Abell 1631 , X–ray data suggest the presence of a hot intergalactic medium related to the group to the X–ray emission detected .
The present results are discussed in the context of group evolution .