Frequency domain magnetic resonance spectroscopy on [Mn₁₂]^− and [Mn₉]: Zero-field splittings and lineshape analysis

详细信息    查看全文

• 作者：Nadeschda Kirchner ; Joris van Slageren ; Euan K. Brechin and Martin Dressel
• 关键词：Single molecule magnets ; Electron paramagnetic resonance ; Manganese
• 刊名：Polyhedron
• 出版年：2005
• 出版时间：2005
• 年：2005
• 卷：24
• 期：16-17
• 页码：2400-2404
• 全文大小：151 K

文摘

The zero-field splitting parameters of two non-integer spin state single molecule magnets were determined using frequency domain magnetic resonance spectroscopy: D = −0.454 ± 0.004 cm^−1, 2"">2&_user=10&_cdi=5276&_rdoc=58&_handle=V-WA-A-W-AVY-MsSAYZA-UUA-U-AABZBZYBEB-AABBEVEAEB-CAYDEUUAY-AVY-U&_acct=C000050221&_version=1&_userid=10&md5=d507fd396b011c6161d9792a900d0f9e"">230> for [Mn₁₂]^−, and D = −0.247 ± 0.005 cm^−1, 276&_rdoc=58&_handle=V-WA-A-W-AVY-MsSAYZA-UUA-U-AABZBZYBEB-AABBEVEAEB-CAYDEUUAY-AVY-U&_acct=C000050221&_version=1&_userid=10&md5=8c3bb13d39d571791cbfb6050f3cdf99"">20 width=214> for [Mn₉]. The linewidth of the magnetic resonance lines is determined by distributions in the zero-field splitting parameters in the case of [Mn₉], leading to a Gaussian lineshape. Interestingly, the resonance line is homogeneously broadened in the case of [Mn₁₂]^−, which is one of the few examples in single molecule magnetism. This means that the linewidth is determined by the excited spin state lifetime, which can be calculated to be 50–58 ps depending on the temperature.