Preferred Label : cis conformation;
Detailed label : cis conformation in polymers;
IUPAC definition : Conformations referring to torsion angles θ (A, B, C, D), where A, B, C, D are main-chain
atoms, can be described as: i cis /i or synperiplanar (C); gauche or synclinal (G);
anticlinal (A); and i trans /i or antiperiplanar (T), corresponding to torsion angles
within 30 of, respectively, 0 , 120 and 180 . The letters shown in parentheses
(upper case C, G, A, T) are the recommended abbreviations. The symbols G , G- (or
A , G-, for example) refer to torsion angles of similar type but opposite known sign,
i.e. 60 , -60 (or 120 , -120 ). The notation G, G(bar) ; A, A(bar) (and T,
T(bar) ; C, C(bar) - whenever the torsion angles are not exactly equal to 180 and
0 , respectively) is reserved for the designation of enantiomorph conformations, i.e.
conformations of opposite but unspecified sign. Where necessary, a deviation from
the proper value of the torsion angle can be indicated by the sign ( ), as in the
following examples: G( ); G ( ); G - ( ).;
Origin ID : C01088;
See also
Conformations referring to torsion angles θ (A, B, C, D), where A, B, C, D are main-chain
atoms, can be described as: i cis /i or synperiplanar (C); gauche or synclinal (G);
anticlinal (A); and i trans /i or antiperiplanar (T), corresponding to torsion angles
within 30 of, respectively, 0 , 120 and 180 . The letters shown in parentheses
(upper case C, G, A, T) are the recommended abbreviations. The symbols G , G- (or
A , G-, for example) refer to torsion angles of similar type but opposite known sign,
i.e. 60 , -60 (or 120 , -120 ). The notation G, G(bar) ; A, A(bar) (and T,
T(bar) ; C, C(bar) - whenever the torsion angles are not exactly equal to 180 and
0 , respectively) is reserved for the designation of enantiomorph conformations, i.e.
conformations of opposite but unspecified sign. Where necessary, a deviation from
the proper value of the torsion angle can be indicated by the sign ( ), as in the
following examples: G( ); G ( ); G - ( ).
