TY - JOUR
T1 - Coordination structure conversion of protonated bisporphyrinato terbium(iii) double-decker complexes and creation of a Kondo assembly by electron injection on the Au(111) surface
AU - Inose, Tomoko
AU - Tanaka, Daisuke
AU - Liu, Jie
AU - Kajihara, Mizu
AU - Mishra, Puneet
AU - Ogawa, Takuji
AU - Komeda, Tadahiro
N1 - Funding Information:
The authors thank Prof. Hirofumi Tanaka (Kyushu Institute of Technology) for fruitful discussions about the results. This study was supported in part by the JSPS KAKENHI Grant No. 24651142 and 25706005, and Grant-in-Aid for Scientific Research (B) (No. 16H04191 for TK) and Exploratory Research (No. 17K19047 for TK). In addition, it was supported by a Grant-in-Aid for Scientific Research on the Innovative Area "Molecular Architectonics: Orchestration of Single Molecules for Novel Functions" from the Ministry of Education, Culture, Science, Sports, and Technology of Japan (No. 25110002 and No. 25110005). The work was also supported by a Grant-in-Aid for JSPS Fellows (No. A2615190 and 16H03863).
Funding Information:
The authors thank Prof. Hirofumi Tanaka (Kyushu Institute of Technology) for fruitful discussions about the results. This study was supported in part by the JSPS KAKENHI Grant No. 24651142 and 25706005, and Grant-in-Aid for Scientific Research (B) (No. 16H04191 for TK) and Exploratory Research (No. 17K19047 for TK). In addition, it was supported by a Grant-in-Aid for Scientific Research on the Innovative Area “Molecular Architectonics: Orchestration of Single Molecules for Novel Functions” from the Ministry of Education, Culture, Science, Sports, and Technology of Japan (No. 25110002 and No. 25110005). The work was also supported by a Grant-in-Aid for JSPS Fellows (No. A2615190 and 16H03863). We would like to thank Editage (http://www.editage.jp) for English language editing.
Publisher Copyright:
© 2018 The Royal Society of Chemistry.
PY - 2018/11/7
Y1 - 2018/11/7
N2 - The first step towards the synthesis of single-molecule magnet (SMM)-based spintronics devices is the organization and manipulation of magnetic molecules on surfaces. Our previous studies on bulk crystals demonstrated that protonated porphyrinato double-decker complexes [Tb(Hoep)(oep)] (oep = 2,3,7,8,12,13,17,18-octaethylporphyrinato) are not SMMs; however, once a hydrogen is removed to produce their neutral radical forms, [Tb(oep)2], they convert to SMMs. These intriguing properties encouraged us to examine the electronic/spin properties of these complexes and their chemical conversion ability after their transfer onto a metal substrate, similar to the environment required for the practical application of SMMs. Herein, we conducted a single-molecule-scale conversion of the protonated bis(porphyrinato)terbium(iii) double-decker complex [Tb(Hoep)(oep)], whose hepta-coordinated terbium ion changes into octa-coordinated [Tb(oep)2] on detaching a hydrogen atom by scanning tunnelling microscopy. This conversion can be caused by the injection of tunnelling electrons of energy 1.5-2.5 eV. We confirmed the conversion by analysing the topographic image and the spin state of the molecule. The latter was achieved by examining the Kondo resonance, which originated from the screening of the molecular spin by the conduction electrons of the metal. The Kondo resonance was not observed for [Tb(Hoep)(oep)] but was observed for the converted species, which agrees well with a model containing the [Tb(oep)2] molecule and Kondo resonance originating from the π-electron spin of the porphyrin ligand. Even though it is not possible to provide complete evidence of the SMM properties of the transferred molecule, we have demonstrated a possible path to realize the switch-on SMM properties of a single molecule.
AB - The first step towards the synthesis of single-molecule magnet (SMM)-based spintronics devices is the organization and manipulation of magnetic molecules on surfaces. Our previous studies on bulk crystals demonstrated that protonated porphyrinato double-decker complexes [Tb(Hoep)(oep)] (oep = 2,3,7,8,12,13,17,18-octaethylporphyrinato) are not SMMs; however, once a hydrogen is removed to produce their neutral radical forms, [Tb(oep)2], they convert to SMMs. These intriguing properties encouraged us to examine the electronic/spin properties of these complexes and their chemical conversion ability after their transfer onto a metal substrate, similar to the environment required for the practical application of SMMs. Herein, we conducted a single-molecule-scale conversion of the protonated bis(porphyrinato)terbium(iii) double-decker complex [Tb(Hoep)(oep)], whose hepta-coordinated terbium ion changes into octa-coordinated [Tb(oep)2] on detaching a hydrogen atom by scanning tunnelling microscopy. This conversion can be caused by the injection of tunnelling electrons of energy 1.5-2.5 eV. We confirmed the conversion by analysing the topographic image and the spin state of the molecule. The latter was achieved by examining the Kondo resonance, which originated from the screening of the molecular spin by the conduction electrons of the metal. The Kondo resonance was not observed for [Tb(Hoep)(oep)] but was observed for the converted species, which agrees well with a model containing the [Tb(oep)2] molecule and Kondo resonance originating from the π-electron spin of the porphyrin ligand. Even though it is not possible to provide complete evidence of the SMM properties of the transferred molecule, we have demonstrated a possible path to realize the switch-on SMM properties of a single molecule.
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U2 - 10.1039/c8nr04630a
DO - 10.1039/c8nr04630a
M3 - Article
C2 - 30307449
AN - SCOPUS:85055601660
SN - 2040-3364
VL - 10
SP - 19409
EP - 19417
JO - Nanoscale
JF - Nanoscale
IS - 41
ER -