Sequential double second-order nonlinear optical switch by an acido-triggered photochromic cyclometallated...

Area of Science:

• Coordination Chemistry
• Materials Science
• Nonlinear Optics

Background:

• Nonlinear optical (NLO) materials are crucial for advanced photonic applications.
• Developing multi-responsive NLO materials remains a significant challenge.
• Platinum(II) complexes offer tunable electronic and photophysical properties.

Purpose of the Study:

• To present a novel dinuclear platinum(II) complex with sequential dual-responsive NLO switching capabilities.
• To demonstrate the unprecedented functionality of this complex as a double nonlinear optical switch.

Main Methods:

• Synthesis and characterization of the dinuclear platinum(II) complex (2(o)).
• Investigation of nonlinear optical properties using Z-scan techniques.
• Protonation studies and UV-Vis absorption spectroscopy.
• Photophysical characterization including luminescence and excited-state dynamics.

Main Results:

• The complex 2(o) exhibits significant nonlinear optical responses.
• Protonation induces a distinct change in the NLO properties, acting as the first switching event.
• Subsequent UV light irradiation triggers a second, independent NLO switching event.
• The sequential switching is reversible and tunable.

Conclusions:

• The presented dinuclear platinum(II) complex is the first example of a sequential double nonlinear optical switch.
• This system demonstrates a novel mechanism for controlling NLO properties through sequential external stimuli.
• The findings open avenues for designing sophisticated optical switches and logic gates for photonic devices.