Ammonothermal Synthesis, Crystal Structure, And Properties Of The Ytterbium(Ii) And Ytterbium(Iii) Amides And The First Two Rare-Earth-Metal Guanidinates, Ybc(Nh)(3) And Yb(Cn3h4)(3)

We report the oxidation-controlled synthesis of the ytterbium amides Yb(NH2)(2) and Yb(NH2)(3) and the first rare-earth metal guanidinates YbC(NH2)(2), and Yb(CN3H4)(3) from liquid ammonia. For Yb(N1-12)2, we present experimental atomic displacement parameters from powder X-ray diffraction (PXRD) and density functional theory (DFT)-derived hydrogen positions for the first time. For Yb(NH2)(3), the indexing proposal based on PXRD arrives at R (3) over bar, a = 6.2477(2) angstrom, c = 17.132(1) angstrom, V = 579.15(4) angstrom(3), and Z = 6. The oxidation-controlled synthesis was also applied to make the first rare-earth guanidinates, namely, the doubly deprotonated YbC(NH)(3) and the singly deprotonated Yb(CN3H4)(3). YbC(NH)(3) is isostructural with SrC(NH)(3), as derived from PXRD (P6(3)/m, a = 5.2596(2) angstrom, c = 6.6704(2) angstrom, v = 159.81(1) angstrom(3), and Z = 2). Yb(CN3H4)(3) crystallizes in a structure derived from the [ReO3] type, as studied by powder neutron diffraction (Pn (3) over bar, a = 13.5307(3) angstrom, v = 2477.22(8) angstrom(3), and Z = 8 at 10 K). Electrostatic and hydrogen-bonding interactions cooperate to stabilize the structure with wide and empty channels. The IR spectra of the guanidinates are compared with DFT-calculated phonon spectra to identify the vibrational modes. SQUID magnetometry shows that Yb(CN3H4)(3) is a paramagnet with isolated Yb3+ (4f(13)) ions. A CONDON 2.0 fit was used to extract all relevant parameters.