Structure of a thallium(I) transition-metal carbonyl salt Tl[Fe(CO)3(NO)]

The Electronic Ground State of [Fe(CO)3(NO)]−: A Spectroscopic and Theoretical Study

“…[14] Bond lengths and angles in [Fe(CO) 3 (NO)] À were obtained that are in good agreement with experimental data derived from X-ray crystallography. [9] Furthermore, both EXAFS in solid phase and in solution (THF) were in good agreement with the Fe À C and Fe À N distances ( Table 1).…”

“…If the NO ligand is considered to be cationic, the iron in the complex ferrate [Fe(CO) 3 (NO)] À should have an oxidation state of ÀII. However, two of the reported spectroscopic properties are not in line with this assignment: a) a NÀO bond length of 1.212 , [9] and b) a NO signal in the IR spectrum at 1647 cm À1 . [10] These properties indicate the NO ligand may not be cationic but in a reduced form.…”

“…We started our investigation with a validation of the unusual NÀO distance [9] and of the small IR NO signal [10] using DFT methods and additional spectroscopic measurements. The BP86 functional [11] with the def-TZVP basis set [12] and COSMO [13] (Mçssbauer parameters were used to generate calibration data using COSMO (e = 80)) proved to be the method of choice.…”

Der elektronische Grundzustand von [Fe(CO)3(NO)]−: eine spektroskopische und theoretische Studie

“…Wir haben in den letzten Jahren über eine Vielzahl [Fe(CO) 3 (NO)] À -katalysierter Reaktionen berichtet. [3,7] Dabei beobachteten wir, dass das formal isoelektronische Collman-Reagens, [8] [9] und b) eine NO-Bande im IR-Spektrum von 1647 cm À1 . [10] Diese Eigenschaften lassen vielmehr auf einen reduzierten NO-Liganden schließen, der klassisch jedoch nicht linear gebunden vorliegen sollte.…”

The Evolution of Fe‐catalyzed Nucleophilic Activation of Acceptor‐substituted Vinyl‐ and Arylcyclopropanes

“…The NO ligand of [Fe(CO) 3 (NO)] − is normally considered to be cationic, and the oxidation state of iron is therefore said to be −II. However, according to the literature, this N−O has a bond length of 1.212 Å, and the NO signal in the IR spectrum appears at 1647 cm −1 , while being bound to the metal center in an almost linear fashion. The deviation of the structural parameters from the values one would expect for a cationic NO ligand attracted our attention, and we performed a combined spectroscopic and quantum chemical investigation .…”