Long wavelength voltage sensitive dyes

A compound comprising the structure of Formula II:

• wherein,
• A1 is selected from SiH2, SiHR′, or SiR′2, wherein R′ is selected from the group consisting of D, optionally substituted FG, optionally substituted (C1-C12)alkyl, optionally substituted (C1-C11)heteroalkyl, optionally substituted (C1-C12)alkenyl, optionally substituted (C1-C11)heteroalkenyl, optionally substituted (C1-C12)alkynyl, and optionally substituted (C1-C11)heteroalkynyl;
• X1-X11 are independently selected from N or C, wherein when an X group is an N, then the R group is absent;
• and
• R1-R15 are independently selected from H, D, optionally substituted FG, optionally substituted (C1-C12)alkyl, optionally substituted (C1-C11)heteroalkyl, optionally substituted (C1-C12)alkenyl, optionally substituted (C1-C11)heteroalkenyl, optionally substituted (C1-C12)alkynyl, optionally substituted (C1-C11)heteroalkynyl, optionally substituted cycloalkyl, optionally substituted cycloalkenyl, optionally substituted aryl, optionally substituted heterocycle, optionally substituted mixed ring system, wherein one or more adjacent R groups can be linked together to form one or more substituted rings selected from the group comprising cycloalkyl, cycloalkenyl, heterocycle, aryl, and mixed ring system,
• W1 is a molecular wire moiety;
• and
• wherein one of R1 or R5 is a sulfonate group.