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Chiral -ITV framework with P4132 (top) or P4332 (bottom) enantiomorphic space groups, showing the helicoidal chain units (in the three directions, like spiral staircases, dashed rectangles) with right-hand and left-hand helices, respectively, turning 90° in clockwise (+90°) or anticlockwise (−90°) directions (viewed from top to bottom).
