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2007年06月22日

【期刊论文】Hydrolysis Theory for Cisplatin and Its Analogues Based on Density Functional Studies

游效曾

，-0001，（）：

-1年11月30日

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2007年06月22日

【期刊论文】Systematic Theoretical Study of Structures and Bondings of the Charge-Transfer Complexes of Ammonia with HX, XY, and X2 (X and Y are Halogens)

游效曾

，-0001，（）：

-1年11月30日

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2005年03月08日

【期刊论文】A Novel Bis(trans-thiocyanate)iron(II) Spin-Transition Molecular Material with Bidentate Triaryltriazole Ligands and Its Bis(cis-thiocyanate)iron(II) High-Spin Isomer

游效曾， Dunru Zhu， † Yan Xu， † Zhi Yu， † Zijian Guo， † Hai Sang， ‡ Tao Liu， § and Xiaozeng You*， †

，-0001，（）：

-1年11月30日

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Two novel complexes trans-[Fe(MBPT)2(NCS)2] (1) and cis-[Fe(mMBPT)2(NCS)2] (2) have been synthesized and their structure characterized at 293 K by single-crystal X-ray crystallography [MBPT (or mMBPT)=4-p(or m)-methylphenyl-3,5-bis(pyridin-2-yl)-1,2,4-triazole]. Complexes 1 and 2 are isomers, and 1 crystallizes in the triclinic space group P1h with Z=1, a=9.120(3)Å, b=9.2563(18) Å, c=11.576(2) Å, α=76.256(15)°, β=76.405-(18)°, γ=84.983(19)°, and V=922.1(4) Å3 in contrast to 2 in the monoclinic space group C2/c with Z=4, a=21.851(3) Å, b=13.4113(15) Å, c=16.859(3) Å, β=128.153(9)°, and V =3885.0(9) Å3. Both complexes have a similar pseudo-octahedral [FeN6] core with the NCS-groups in the trans arrangement in 1 but cis in 2. Variable-temperature magnetic susceptibility and IR spectral measurements reveal that 1 shows an abrupt high-spin T low-spin (HS T LS) transition centered at T1/2 around 231 K, in contrast to 2 staying in a high-spin state in the observed temperature range of 75-300 K. The extended X-ray absorption fine structures (EXAFS) spectra confirm that the average Fe-N distance for the HS state in 1 is 0.2 Å longer than that of the LS state. Complex 1 represents the first spin-crossover iron(II) complex with triaryltriazole and trans-thiocyanate ligands.