High-temperature photo-induced switching and pressure-induced transition in a cooperative molecular spin-crossover material.
نویسندگان
چکیده
The thermal and photo-induced switching properties of the recently published molecular spin crossover complex [Fe(H4L)2](ClO4)2·H2O·2(CH3)2CO () have been investigated in detail through Raman spectroscopy. Magnetometric and single crystal X-ray diffraction kinetic studies within the hysteresis loop have proven its metastable character, which allowed establishing the shape of the true, quasi-static hysteresis loop. This is related to the proximity of the temperatures of the thermal high to low spin SCO (T1/2↓) to those of the relaxation of the thermally or photo-generated metastable states (T(TIESST) and T(LIESST), respectively). Green light irradiation within the hysteresis loop results in a complete low to high spin photo-switch. In addition, the SCO of at room temperature can be induced by applying pressure, as followed by Raman spectroscopy.
منابع مشابه
Cooperative elastic switching vs. laser heating in [Fe(phen)2(NCS)2] spin-crossover crystals excited by a laser pulse.
Spin-crossover crystals show multi-step responses to femtosecond light excitation. The local molecular photo-switching from low to high spin states occurs on sub-picosecond timescale. It is followed by additional conversion due to elastic (ns) and thermal (μs) effects. In [Fe(phen)2(NCS)2] crystals discussed herein, the thermal switching can be made unobtrusive for the investigation of cooperat...
متن کاملLight-induced excited spin state trapping effect on [Fe(mepy)3tren](PF6)2 solvated crystals.
A spin-crossover solvated compound [Fe(mepy)3tren](PF6)2·C7H8·C2H3N has been prepared and its switching properties have been compared to those reported for the non-solvated solid. The thermal spin transition occurs at 88 K with the opening of a 3.5 K wide hysteresis loop, while a fairly steep transition at 215 K without hysteresis has been previously reported for the non-solvated analogue. This...
متن کاملPressure and Temperature Spin Crossover Sensors with Optical Detection
Iron(II) spin crossover molecular materials are made of coordination centres switchable between two states by temperature, pressure or a visible light irradiation. The relevant macroscopic parameter which monitors the magnetic state of a given solid is the high-spin (HS) fraction denoted n(HS), i.e., the relative population of HS molecules. Each spin crossover material is distinguished by a tra...
متن کاملBudding Researchers Support Proposal Report
Purpose of the experiment: The materials with light-triggered and/or -driven function have been attractive in creating a novel conceptual function. To investigate those structures not only understand the mechanism of photo-induced phenomena but also lead new design of optical functional materials. For reasons detailed below, we focus on one of spin crossover complexes t-[Fe(abpt)2(NCS)2] polymo...
متن کاملPressure-induced spin crossover in ferropericlase: an alternative concept
Ferropericlase (Mg,Fe)O is the second most abundant mineral in the Earth’s lower mantle after (Mg,Fe)SiO3 perovskite. Its high-pressure and high-temperature properties are crucial for the determination of the Earth’s deep interior model. The hypothesis of a pressure-induced spin transition of Fe ions in geologically relevant materials was proposed more than 40 years ago [1], but the experimenta...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Dalton transactions
دوره 43 2 شماره
صفحات -
تاریخ انتشار 2014