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HERO ID
3994000
Reference Type
Journal Article
Title
Field-Induced Co(II) Single-Ion Magnets with mer-Directing Ligands but Ambiguous Coordination Geometry
Author(s)
Peng, Y; Mereacre, V; Anson, CE; Zhang, Y; Bodenstein, T; Fink, K; Powell, AK
Year
2017
Is Peer Reviewed?
Yes
Journal
Inorganic Chemistry
ISSN:
0020-1669
EISSN:
1520-510X
Volume
56
Issue
11
Page Numbers
6056-6066
Language
English
PMID
28485955
DOI
10.1021/acs.inorgchem.6b02743
Web of Science Id
WOS:000402950600007
URL
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85020291079&doi=10.1021%2facs.inorgchem.6b02743&partnerID=40&md5=9de0c32b9ed483bc16d4decc03565c56
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Abstract
Three air-stable Co(II) mononuclear complexes with different aromatic substituents have been prepared and structurally characterized by single-crystal X-ray diffraction. The mononuclear complexes [Co(H2L1)2]·2THF (1), [Co(HL2)2] (2), and [Co(H2L3)2]·CH2Cl2 (3) (where H3L1, H2L2, and H3L3 represent 3-hydroxy-naphthalene-2-carboxylic acid (6-hydroxymethyl-pyridin-2-ylmethylene) hydrazide, nicotinic acid (6-hydroxymethyl-pyridin-2-ylmethylene) hydrazide, and 2-hydroxy-benzoic acid (6-hydroxymethyl-pyridin-2-ylmethylene) hydrazide, respectively) feature a distorted mer octahedral coordination geometry. Detailed magnetic studies of 1-3 have been conducted using direct and alternating current magnetic susceptibility data. Field-induced slow magnetic relaxation was observed for these three complexes. There are few examples of such behavior in (distorted) octahedral coordination geometry (OC) Co(II) mononuclear complexes with uniaxial anisotropy. Analysis of the six-coordinate Co(II) mononuclear single-ion magnets (SIMs) in the literature using the SHAPE program revealed that they all show what is best described as distorted trigonal prismatic (TRP) coordination geometry, and in general, these show negative D zero-field splitting (ZFS) values. On the other hand, all the Co(II) mononuclear complexes displaying what is best approximated as distorted octahedral (OC) coordination geometry show positive D values. In the new Co(II) mononuclear complexes we describe here, there is an ambiguity, since the rigid tridentate ligands confer what is best described for an octahedral complex as a mer coordination geometry, but the actual shape of the first coordination sphere is between octahedral and trigonal prismatic. The negative D values observed experimentally and supported by high-level electronic structure calculations are thus in line with a trigonal prismatic geometry. However, a consideration of the rhombicity as indicated by the E value of the ZFS in conjunction with the SHAPE analysis shows that in this case it is difficult to distinguish between the OC and TRP descriptions.
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IRIS
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Cobalt
LitSearch: January 2008 - August 2018
WoS
•
Naphthalene
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PubMed
Combined data set
Data set for title/abstract screening
Excluded - PECO criteria not met (TIAB)
October 2017 Update
PubMed
Other
•
Naphthalene (2021 Evidence mapping publication)
Database Searches
PubMed
Combined data set
Data set for title/abstract screening
Excluded – PECO criteria not met
October 2017 Update
PubMed
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