The present invention relates to compounds represented by the following Formula Ic, in which R2-R6 can each independently be selected from hydrogen or hydrocarbyl (e.g., methyl); L1 and L4 are each independently a divalent linking group, such as a bond or —OC(O)—R8—C(O)O—, where R8 can be divalent hydrocarbyl (e.g., —CH2CH2—); each L2 and each L5 each independently represent a flexible segment, such as divalent linear or branched C1-C25 alkyl; each L3 and each L6 each independently represent a rigid segment including, for example, optionally substituted phenylen-1,4-diyl groups; t and s are each independently from 1 to 4; m and p are each independently from 0 to 4 for each t, provided that the sum of m and p is at least 1 for each t; q and r are each independently from 0 to 4 for each s, provided that the sum of q and r is at least 1 for each s; and E1 and E2 can each independently be hydrogen or hydrocarbyl. The present invention also relates to compositions, such as liquid crystal compositions, and articles, such as optical elements, that include the compound represented by Formula Ic.