Solid‐State Reversible Quadratic Nonlinear Optical Molecular Switch with an Exceptionally Large Contrast

Abstract

Exceptional nonlinear optical (NLO) switching behavior, including an extremely large contrast (on/off) of ∼35 and high NLO coefficients, is displayed by a solid-state reversible quadratic NLO switch. The favorable results, induced by very fast molecular motion and anionic ordering, provides impetus for the design of a novel second-harmonic-generation switch involving molecular motion.

[C5H12N]SnCl3: A Tin Halide Organic–Inorganic Hybrid as an Above‐Room‐Temperature Solid‐State Nonlinear Optical Switch

“…Sharp anomalous peaks of the observed thermal anomalies during successive heating and cooling cycles revealed that MPSC exhibits a first‐order‐type phase transition with an estimated entropy change (Δ S ) of aprroximately 12.3 J mol −1 K −1 at 383 K. In addition, according to the Boltzmann equation, Δ S = R ln N , in which R is the gas constant (8.314 J mol −1 K −1 ) and N is the number of possible orientations for the disordered system, the calculated value of N is 4.39, which reveals that MPSC undergoes a complex order/disorder phase transition during the temperature variation. It is known that structural phase transitions are always associated with molecular dipole motions, which are accompanied by evident dielectric anomalies ,. Figure b shows the real part ( ϵ ) of the complex dielectric permittivity as a function of temperature for the MPSC crystal at frequencies of 200, 500, and 1 MHz.…”

Second-order nonlinear optical switching with a record-high contrast for a photochromic and thermochromic bistable crystal

“…Luo’s group9,38–43 found that thermally induced order–disorder phase transitions of DABCO salts (DABCO = 1,4-diazabicyclo[2.2.2]octane), crown ether derivatives and propanediol analogues resulted in SHG-switching contrasts of 12–150 times. Mercier’s group reported that organic disulfide-based metal halides displayed thermoswitching of SHG signals from active to silent due to conglomerate-to-racemate transition 4,37.…”

Crystal structure and phase transition of 2-methoxyanilinium perchlorate-18-crown-6

“…3a). The 18-crown-6 molecule is highly orientationally disordered over two positions with occupation factors of 0.581(4) and 0.419 (4). To facilitate the explanation, we denote 18-crown-6 with the occupation factor of 0.581(4) by RTPa and 18-crown-6 with the occupation factor of 0.419(4) by RTPb.…”

“…Searching for new solid-to-solid phase transitions triggered by temperature is very important not only for the exploration of novel physical properties but also theoretically for the study of structure-property relationships [1][2][3][4][5]. Recently, a series of research has been conducted on phase transitions in organic and inorganic hybrid complexes, which possess the properties of both organic and inorganic compounds [6][7][8][9].…”