Severity: Warning
Message: file_get_contents(https://...@pubfacts.com&api_key=b8daa3ad693db53b1410957c26c9a51b4908&a=1): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 176
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 176
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 250
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3122
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 575
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 489
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
The reaction of K3[Cr(CN)6] and the copper(II) bis-diamino complex of the ligand 1,3-diaminopropane (tn) led to the new cyanide-bridged 3D polymer ([(Cu(tn)2)3(Cr(CN)6)][Cr(CN)6]) infinity (1). Crystallographic data for 1: trigonal space group R3, a = b = 15.4908(11), c = 16.7699(13) angstroms, Z = 3, V = 3485.0(4) angstroms3. By the same reaction using trans-cyclohexane-(1R,2R)-diamine [1R,2Rchxn] or trans-cyclohexane-(1S,2S)-diamine [1S,2Schxn] as ligands, the chiral 1D polymers ([Cu(1R,2Rchxn)2]3[Cr(CN)6]2.4.75H2O) infinity (2) and ([Cu(1S,2Schxn)2]3[Cr(CN)6]2.4.25H2O} infinity (3), respectively, were obtained. 2 and 3 are isostructural and crystallize in the triclinic space group P1, with a = 8.5421(6), b = 12.6379(9), c = 16.1571(11) angstroms, alpha = 104.594(5) degrees , beta = 98.425(6) degrees , gamma= 97.440(5) degrees , Z = 1, V = 1644.3(2) angstroms3 for 2, and a = 8.5435(8), b = 12.6309(12), c = 16.1711(17) angstroms, alpha = 104.632 degrees , beta = 98.429(8) degrees , gamma = 97.375(8) degrees , Z = 1, and V = 1645.1(3) angstroms3 for 3. The complexes have been characterized by X-ray crystallography, IR, and magnetic susceptibility measurements. The chirality of 2 and 3 has been confirmed by circular dichroism measurements in the solid state. From the magnetic point of view, 1 shows 3D ferromagnetic ordering at ca. 4K, and 2 shows a weak intrachain ferromagnetic exchange, as a result of magnetic orbital orthogonality between Cr(III) and Cu(II) in the chain, with very long Cu-N(cyano) distances (2.665(5) and 2.671(5) angstroms) due to the long Jahn-Teller axis of the copper(II) ions.
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http://dx.doi.org/10.1021/ic702234y | DOI Listing |
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