臺灣博碩士論文加值系統

本篇論文, 利用兩種不同電子效應之苯環對位取代基之卜林及以水楊醛及
安類縮合反應合成之L1, L2, 兩種不同系列之配位基, 分別與鐵離子形成
氧架橋雙核鐵(III)錯合物, Fe(III)-O-Fe(III),再將Fe(III)-O-Fe(III)
以HPF6或HBF4部份氧化成Fe(III)-O-Fe(IV)混價錯合物. 首先以各種物理
方法鑑定此類配位基及鹽類之組成,化學鍵結狀態及單晶結構外, 主要以
變溫磁性及變溫梅思堡光譜探討錯合物中鐵的原子價態.在這篇研究中,
得到 Fe(L2)Cl 及 [Fe(TTP)]2O 兩個單晶結構 , 分別屬於單斜晶系及三
角晶系, 空間對稱群為 P21/c (Z=8)及 P31 (Z=3), Fe(III)-O-Fe(III)
及 Fe(III)-O-Fe(IV) 兩系列錯合物之紅外光譜皆有 800 ~ 900 cm-1 位
置之Fe-O-Fe特徵吸收. 以 EPR 光譜可觀測到 g~2 處具有鐵(III)離子同
向性的吸收訊號.由變溫磁性數據,發現兩系列錯合物均具反鐵磁性交換作
用.以最小平方精算法依磁交換理論公式 ( H=-2J S1 S2, S1= S2=5/2 ;
S1=5/2, S2=2 ), 求得最佳適模. Fe(III)-O-Fe(III)系列之磁交換常
數 J 範圍為 -183 ~ 92 cm-1, 而 Fe(III)- O-Fe(IV) 系列之J 值範圍
則為 -95.5 ~ -32.9 cm-1.利用鐵(57)變溫梅思堡光譜可確認兩系列錯合
物中之鐵原子均為高自旋狀態, Fe(III)-O-Fe(IV) 錯合物之光譜圖清楚
地觀測到分屬不同的鐵原子吸收峰, 為鐵(III)鐵(IV)混價錯合物的特性.

In the present thesis, two series oxo-bridge Fe(III) com-
plexes with the ligands of the meso substituents of porp- rins
and L1, L2(which are prepared from schiff-base cond- ensation
reactions.) and the partial oxidazed of Fe(III)- O-Fe(III)
complexes with HPF6 or HBF4 to form Fe(III)-O- Fe(IV) mix-
valence compounds have been prepared. Their structatures,
valence states of iron atom and magnetic peoperties have been
investigated by means of X-ray diffr- actometry, Mossbauer, EPR
and magnetic susceptibility mea- surements. Crystal of [Fe(L2)
Cl] and [Fe(TTP)]2O show the space group of P21/c (Z=8) and P31
(Z=3). Two series of complexes both exhibit asymmetric Fe-O-Fe
band in IR spectra and isotropic with g~2 at 298 K. An
antiferromagnetic exchange interaction in the present complexes
resvealed from variable-temperature (5K ~ 300K) magnetic
susceptibility data, which can be least-squares fit to the
theoretical equation for an isotropic exchange interaction (
H=-2J S1 S2 ) in S1=S2=5/2 for Fe(III)-O- Fe(III) and S1=5/2,
S2=2 for Fe(III)-O-Fe(IV) dimer. The exchange parameter, J, for
the Fe(III)-O-Fe(III) compounds are in the range of -183 cm-1 ~
92.5 cm-1 and for the mix- valence compounds are -95.5 cm-1 ~
-32.95 cm-1. The Mossbauer spectra of Fe(III)--O-Fe(III) and Fe(
III)- O-Fe(IV) complexes have been measures at 298K and 80K. A
single, temperature-independence, quarupole-split absor- ption
is observered for the Fe(III)-O-Fe(III) compounds. Fe(III)-O-Fe(
IV) show two well-resolved, reasonably asy- mmetric doublet
peaks are characteristic of Fe(III)-O- Fe(IV) mix-valence
compounds.