DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Cation-poor complex metallic alloys in Ba(Eu)–Au–Al(Ga) systems: Identifying the keys that control structural arrangements and atom distributions at the atomic level

Abstract

Four complex intermetallic compounds BaAu6±xGa6±y (x = 1, y = 0.9) (I), BaAu6±xAl6±y (x = 0.9, y = 0.6) (II), EuAu6.2Ga5.8 (III), and EuAu6.1Al5.9 (IV) have been synthesized, and their structures and homogeneity ranges have been determined by single crystal and powder X-ray diffraction. Whereas I and II originate from the NaZn13-type structure (cF104–112, Fm3C), III (tP52, P4/nbm) is derived from the tetragonal Ce2Ni17Si9-type, and IV (oP104, Pbcm) crystallizes in a new orthorhombic structure type. Both I and II feature formally anionic networks with completely mixed site occupation by Au and triel (Tr = Al, Ga) atoms, while a successive decrease of local symmetry from the parental structures of I and II to III and, ultimately, to IV correlates with increasing separation of Au and Tr on individual crystallographic sites. Density functional theory-based calculations were employed to determine the crystallographic site preferences of Au and the respective triel element to elucidate reasons for the atom distribution (“coloring scheme”). Chemical bonding analyses for two different “EuAu6Tr6” models reveal maximization of the number of heteroatomic Au–Tr bonds as the driving force for atom organization. The Fermi levels fall in broad pseudogaps for both models allowing some electronic flexibility. Spin-polarized band structure calculationsmore » on the “EuAu6Tr6” models hint to singlet ground states for europium and long-range magnetic coupling for both EuAu6.2Ga5.8 (III) and EuAu6.1Al5.9 (IV). This is substantiated by experimental evidence because both compounds show nearly identical magnetic behavior with ferromagnetic transitions at TC = 6 K and net magnetic moments of 7.35 μB/f.u. at 2 K. As a result, the effective moments of 8.3 μB/f.u., determined from Curie–Weiss fits, point to divalent oxidation states for europium in both III and IV.« less

Authors:
 [1];  [1];  [1];  [1];  [1];  [1]
  1. Iowa State Univ., Ames, IA (United States)
Publication Date:
Research Org.:
Ames Lab., Ames, IA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
OSTI Identifier:
1234462
Report Number(s):
IS-J-8872
Journal ID: ISSN 0020-1669
Grant/Contract Number:  
AC02-07CH11358
Resource Type:
Accepted Manuscript
Journal Name:
Inorganic Chemistry
Additional Journal Information:
Journal Volume: 54; Journal Issue: 21; Journal ID: ISSN 0020-1669
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; complex intermetallics; coloring schemes; structural preferences; magnetism

Citation Formats

Smetana, Volodymyr, Steinberg, Simon, Mudryk, Yaroslav, Pecharsky, Vitalij, Miller, Gordon J., and Mudring, Anja -Verena. Cation-poor complex metallic alloys in Ba(Eu)–Au–Al(Ga) systems: Identifying the keys that control structural arrangements and atom distributions at the atomic level. United States: N. p., 2015. Web. doi:10.1021/acs.inorgchem.5b01633.
Smetana, Volodymyr, Steinberg, Simon, Mudryk, Yaroslav, Pecharsky, Vitalij, Miller, Gordon J., & Mudring, Anja -Verena. Cation-poor complex metallic alloys in Ba(Eu)–Au–Al(Ga) systems: Identifying the keys that control structural arrangements and atom distributions at the atomic level. United States. https://doi.org/10.1021/acs.inorgchem.5b01633
Smetana, Volodymyr, Steinberg, Simon, Mudryk, Yaroslav, Pecharsky, Vitalij, Miller, Gordon J., and Mudring, Anja -Verena. Mon . "Cation-poor complex metallic alloys in Ba(Eu)–Au–Al(Ga) systems: Identifying the keys that control structural arrangements and atom distributions at the atomic level". United States. https://doi.org/10.1021/acs.inorgchem.5b01633. https://www.osti.gov/servlets/purl/1234462.
@article{osti_1234462,
title = {Cation-poor complex metallic alloys in Ba(Eu)–Au–Al(Ga) systems: Identifying the keys that control structural arrangements and atom distributions at the atomic level},
author = {Smetana, Volodymyr and Steinberg, Simon and Mudryk, Yaroslav and Pecharsky, Vitalij and Miller, Gordon J. and Mudring, Anja -Verena},
abstractNote = {Four complex intermetallic compounds BaAu6±xGa6±y (x = 1, y = 0.9) (I), BaAu6±xAl6±y (x = 0.9, y = 0.6) (II), EuAu6.2Ga5.8 (III), and EuAu6.1Al5.9 (IV) have been synthesized, and their structures and homogeneity ranges have been determined by single crystal and powder X-ray diffraction. Whereas I and II originate from the NaZn13-type structure (cF104–112, Fm3C), III (tP52, P4/nbm) is derived from the tetragonal Ce2Ni17Si9-type, and IV (oP104, Pbcm) crystallizes in a new orthorhombic structure type. Both I and II feature formally anionic networks with completely mixed site occupation by Au and triel (Tr = Al, Ga) atoms, while a successive decrease of local symmetry from the parental structures of I and II to III and, ultimately, to IV correlates with increasing separation of Au and Tr on individual crystallographic sites. Density functional theory-based calculations were employed to determine the crystallographic site preferences of Au and the respective triel element to elucidate reasons for the atom distribution (“coloring scheme”). Chemical bonding analyses for two different “EuAu6Tr6” models reveal maximization of the number of heteroatomic Au–Tr bonds as the driving force for atom organization. The Fermi levels fall in broad pseudogaps for both models allowing some electronic flexibility. Spin-polarized band structure calculations on the “EuAu6Tr6” models hint to singlet ground states for europium and long-range magnetic coupling for both EuAu6.2Ga5.8 (III) and EuAu6.1Al5.9 (IV). This is substantiated by experimental evidence because both compounds show nearly identical magnetic behavior with ferromagnetic transitions at TC = 6 K and net magnetic moments of 7.35 μB/f.u. at 2 K. As a result, the effective moments of 8.3 μB/f.u., determined from Curie–Weiss fits, point to divalent oxidation states for europium in both III and IV.},
doi = {10.1021/acs.inorgchem.5b01633},
journal = {Inorganic Chemistry},
number = 21,
volume = 54,
place = {United States},
year = {Mon Oct 19 00:00:00 EDT 2015},
month = {Mon Oct 19 00:00:00 EDT 2015}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 27 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Properties- and applications of quasicrystals and complex metallic alloys
journal, January 2012


Electrical and thermal transport properties of icosahedral and decagonal quasicrystals
journal, January 2012


Complex thermoelectric materials
journal, February 2008

  • Snyder, G. Jeffrey; Toberer, Eric S.
  • Nature Materials, Vol. 7, Issue 2, p. 105-114
  • DOI: 10.1038/nmat2090

Plastic-deformation mechanism in complex solids
journal, February 2010

  • Heggen, M.; Houben, L.; Feuerbacher, M.
  • Nature Materials, Vol. 9, Issue 4
  • DOI: 10.1038/nmat2713

Magnetism in Giant Unit Cells - Crystal Structure and Magnetic Properties of R117Co52+δSn112+γ (R = Sm, Tb, Dy)
journal, May 2011

  • Kovnir, Kirill; Shatruk, Michael
  • European Journal of Inorganic Chemistry, Vol. 2011, Issue 26
  • DOI: 10.1002/ejic.201100200

Structural disorder and magnetism in rare-earth (R) R117Co54+xSn112±y
journal, April 2013


Probing the Lower Limit of Lattice Thermal Conductivity in an Ordered Extended Solid: Gd 117 Co 56 Sn 112 , a Phonon Glass–Electron Crystal System
journal, March 2012

  • Schmitt, Devin C.; Haldolaarachchige, Neel; Xiong, Yimin
  • Journal of the American Chemical Society, Vol. 134, Issue 13
  • DOI: 10.1021/ja300240g

Turning Gold into “Diamond”: A Family of Hexagonal Diamond-Type Au-Frameworks Interconnected by Triangular Clusters in the Sr–Al–Au System
journal, February 2014

  • Palasyuk, Andriy; Grin, Yuri; Miller, Gordon J.
  • Journal of the American Chemical Society, Vol. 136, Issue 8
  • DOI: 10.1021/ja411150e

Polyclusters and Substitution Effects in the Na–Au–Ga System: Remarkable Sodium Bonding Characteristics in Polar Intermetallics
journal, October 2013

  • Smetana, Volodymyr; Miller, Gordon J.; Corbett, John D.
  • Inorganic Chemistry, Vol. 52, Issue 21
  • DOI: 10.1021/ic401580y

Three Alkali-Metal–Gold–Gallium Systems. Ternary Tunnel Structures and Some Problems with Poorly Ordered Cations
journal, April 2012

  • Smetana, Volodymyr; Miller, Gordon J.; Corbett, John D.
  • Inorganic Chemistry, Vol. 51, Issue 14
  • DOI: 10.1021/ic300740u

A Sodium-Containing Quasicrystal: Using Gold To Enhance Sodium’s Covalency in Intermetallic Compounds
journal, November 2012

  • Smetana, Volodymyr; Lin, Qisheng; Pratt, Daniel K.
  • Angewandte Chemie International Edition, Vol. 51, Issue 51
  • DOI: 10.1002/anie.201207076

Hexagonal-Diamond-like Gold Lattices, Ba and (Au,T) 3 Interstitials, and Delocalized Bonding in a Family of Intermetallic Phases Ba 2 Au 6 (Au,T) 3 (T = Zn, Cd, Ga, In, or Sn)
journal, July 2013

  • Lin, Qisheng; Mishra, Trinath; Corbett, John D.
  • Journal of the American Chemical Society, Vol. 135, Issue 30
  • DOI: 10.1021/ja401378q

Gold Network Structures in Rhombohedral and Monoclinic Sr 2 Au 6 (Au,T) 3 (T = Zn, Ga). A Transition via Relaxation
journal, November 2013

  • Mishra, Trinath; Lin, Qisheng; Corbett, John D.
  • Inorganic Chemistry, Vol. 52, Issue 23
  • DOI: 10.1021/ic402145k

Zn 3 and Ga 3 Triangles as Building Units in Sr 2 Au 6 Zn 3 and Sr 2 Au 6 Ga 3 : Zn
journal, September 2013

  • Gerke, Birgit; Hoffmann, Rolf-Dieter; Pöttgen, Rainer
  • Zeitschrift für anorganische und allgemeine Chemie, Vol. 639, Issue 14
  • DOI: 10.1002/zaac.201300366

SrAu4Ga3: a further example with Ga3 units and a Lonsdaleite-related gold substructure
journal, April 2014

  • Seidel, Stefan; Hoffmann, Rolf-Dieter; Pöttgen, Rainer
  • Monatshefte für Chemie - Chemical Monthly, Vol. 145, Issue 7
  • DOI: 10.1007/s00706-014-1205-x

Sr2Au6Al3 and Eu2Au6Al3 – First Representatives of the Sr2Au6Zn3 Type with Aluminum Triangles
journal, January 2014

  • Gerke, Birgit; Pöttgen, Rainer
  • Zeitschrift für Naturforschung B, Vol. 69, Issue 1
  • DOI: 10.5560/znb.2014-3300

Mixed Valent Gold Oxides: Syntheses, Structures, and Properties of Rb5Au3O2, Rb7Au5O2, and Cs7Au5O2
journal, November 2000

  • Mudring, Anja-Verena; Nuss, Jürgen; Wedig, Ulrich
  • Journal of Solid State Chemistry, Vol. 155, Issue 1
  • DOI: 10.1006/jssc.2000.8881

Base-Induced Disproportionation of Elemental Gold
journal, September 2000


Cesiumauride Ammonia (1/1), CsAu⋅NH3: A Crystalline Analogue to Alkali Metals Dissolved in Ammonia?
journal, January 2002


Localized Charge Transfer in CsAu·NH 3 :  1 H and 133 Cs Nuclear Magnetic Resonance
journal, May 2003

  • Krämer, Steffen; Mehring, Michael; Mudring, Anja-Verena
  • The Journal of Physical Chemistry B, Vol. 107, Issue 21
  • DOI: 10.1021/jp022509h

Theoretical Chemistry of Gold
journal, August 2004


Relativistic effects in structural chemistry
journal, May 1988


Neue Ga-Cluster-Verbände im Na 7 Ga 13 -II / New Ga-Cluster Compounds: The Structure of Na 7 Ga 13 -II
journal, February 1982

  • Frank-Cordier, Ursula; Cordier, Gerhard; Schäfer, Herbert
  • Zeitschrift für Naturforschung B, Vol. 37, Issue 2
  • DOI: 10.1515/znb-1982-0202

Na8Au9.8(4)Ga7.2 and Na17Au5.87(2)Ga46.63: The diversity of pseudo 5-fold symmetries in the Na–Au–Ga system
journal, November 2013

  • Smetana, Volodymyr; Corbett, John D.; Miller, Gordon J.
  • Journal of Solid State Chemistry, Vol. 207
  • DOI: 10.1016/j.jssc.2013.08.017

Approximant Phases and an Icosahedral Quasicrystal in the Ca−Au−Ga System: The Influence of Size of Gallium versus Indium
journal, September 2008

  • Lin, Qisheng; Corbett, John D.
  • Inorganic Chemistry, Vol. 47, Issue 17
  • DOI: 10.1021/ic800694j

Development of an Icosahedral Quasicrystal and Two Approximants in the Ca−Au−Sn System: Syntheses and Structural Analyses
journal, November 2010

  • Lin, Qisheng; Corbett, John D.
  • Inorganic Chemistry, Vol. 49, Issue 22
  • DOI: 10.1021/ic101356n

Development of the Ca−Au−In Icosahedral Quasicrystal and Two Crystalline Approximants:  Practice via Pseudogap Electronic Tuning
journal, May 2007

  • Lin, Qisheng; Corbett, John D.
  • Journal of the American Chemical Society, Vol. 129, Issue 21
  • DOI: 10.1021/ja069143x

Approximants in the Ag–In– M and Au–Sn– M ( M = Ca or Rare Earth Metals) Systems
journal, October 2008

  • Morita, Yoshiki; Tsai, An Pang
  • Japanese Journal of Applied Physics, Vol. 47, Issue 10
  • DOI: 10.1143/JJAP.47.7975

Sign of canted ferromagnetism in the quasicrystal approximants Au-SM-R (SM = Si, Ge and Sn / R = Tb, Dy and Ho)
journal, May 2014


Gold-rich R 3 Au 7 Sn 3 : establishing the interdependence between electronic features and physical properties
journal, January 2015

  • Provino, Alessia; Steinberg, Simon; Smetana, Volodymyr
  • J. Mater. Chem. C, Vol. 3, Issue 32
  • DOI: 10.1039/C5TC00884K

Complex Polyanionic Nets in RbAu 4.01(2) Ga 8.64(5) and CsAu 5 Ga 9 : The Role of Cations in the Formation of New Polar Intermetallics : Complex Polyanionic Nets in RbAu
journal, February 2014

  • Smetana, Volodymyr; Corbett, John D.; Miller, Gordon J.
  • Zeitschrift für anorganische und allgemeine Chemie, Vol. 640, Issue 5
  • DOI: 10.1002/zaac.201400015

The Crystal Structure of Alloys of Zinc with the Alkali and Alkaline Earth Metals and of Cadmium with Potassium
journal, August 1937

  • Ketelaar, J. A. A.
  • The Journal of Chemical Physics, Vol. 5, Issue 8
  • DOI: 10.1063/1.1750098

Synthesis and Crystal Structure of LiZn13
journal, June 2010

  • Fischer, Dieter; Jansen, Martin
  • Zeitschrift für anorganische und allgemeine Chemie, Vol. 636, Issue 11
  • DOI: 10.1002/zaac.201000222

The crystal structure of RbZn 13
journal, April 1971

  • Bruzzone, G.
  • Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry, Vol. 27, Issue 4
  • DOI: 10.1107/S0567740871003121

Synthesis and characterization of
journal, November 2005

  • Bailey, Mark S.; McGuire, Michael A.; DiSalvo, Francis J.
  • Journal of Solid State Chemistry, Vol. 178, Issue 11
  • DOI: 10.1016/j.jssc.2005.09.004

Structure of LaFe 9 Si 4 intermetallic compound
journal, October 1994

  • Tang, Wei‐hua; Liang, Jing‐kui; Chen, Xiao‐long
  • Journal of Applied Physics, Vol. 76, Issue 7
  • DOI: 10.1063/1.357359

BaAu x Zn 13– x : Electron-Poor Cubic NaZn 13 -Type Intermetallic and Its Ordered Tetragonal Variant
journal, January 2012

  • Gupta, Shalabh; Corbett, John D.
  • Inorganic Chemistry, Vol. 51, Issue 4
  • DOI: 10.1021/ic2022787

A New[Ni7] Cluster in LaNi7In6 and Distortedbcc Indium Cubes in LaNiIn4
journal, December 2001


∞1[Cu7] Cluster in SrCu7In6— Synthesis and Structure Refinement of a Twinned Crystal
journal, January 2003

  • Zaremba, Vasyl' I.; Muts, Ihor R.; Hoffmann, Rolf-Dieter
  • Zeitschrift für anorganische und allgemeine Chemie, Vol. 629, Issue 1213
  • DOI: 10.1002/zaac.200300239

SrNi 7.90(8) In 5.10(8) – a new superstructure in the NaZn 13 family
journal, September 2009

  • Hoffmann, Rolf-Dieter; Muts, Ihor; Zaremba, Vasyl
  • Zeitschrift für Kristallographie, Vol. 224, Issue 9
  • DOI: 10.1524/zkri.2009.1183

Structure and magnetic properties of EuNi7+xIn6−x
journal, June 2006


New tetragonal derivatives of cubic NaZn13-type structure: RNi6Si6 compounds, crystal structure and magnetic ordering (R=Y, La, Ce, Sm, Gd–Yb)
journal, February 2014


Polar binary Zn/Cd-rich intermetallics: Synthesis, crystal and electronic structure of A(Zn/Cd)13 (A = alkali/alkaline earth) and Cs1.34Zn16
journal, September 2006


Crystal Growth, Structure, and Physical Properties of Ln (Cu,Ga) 13− x ( Ln = La−Nd, Eu; x ≈ 0.2)
journal, July 2009

  • Cho, Jung Young; Thomas, Evan L.; Nambu, Yusuke
  • Chemistry of Materials, Vol. 21, Issue 14
  • DOI: 10.1021/cm803297q

Zinc-deficiency in intermetallics with the NaZn13 type
journal, September 2008


Crystallographic and magnetic behaviour of RCu9Sn4 and RCu9.4Sn3.6 (R=La to Nd) compounds
journal, April 2001


Recent developments in magnetocaloric materials
journal, May 2005

  • Gschneidner, K. A.; Pecharsky, V. K.; Tsokol, A. O.
  • Reports on Progress in Physics, Vol. 68, Issue 6, p. 1479-1539
  • DOI: 10.1088/0034-4885/68/6/R04

Study of the critical behaviour of the magnetization and electrical resistivity in cubic La(Fe, Si)13 compounds
journal, April 1983

  • Palstra, T. T. M.; Mydosh, J. A.; Nieuwenhuys, G. J.
  • Journal of Magnetism and Magnetic Materials, Vol. 36, Issue 3
  • DOI: 10.1016/0304-8853(83)90128-2

Influence of negative lattice expansion and metamagnetic transition on magnetic entropy change in the compound LaFe11.4Si1.6
journal, June 2001

  • Hu, Feng-xia; Shen, Bao-gen; Sun, Ji-rong
  • Applied Physics Letters, Vol. 78, Issue 23
  • DOI: 10.1063/1.1375836

The “Coloring Problem” in Solids: How It Affects Structure, Composition and Properties
journal, May 1998


An empirical correction for absorption anisotropy
journal, January 1995

  • Blessing, R. H.
  • Acta Crystallographica Section A Foundations of Crystallography, Vol. 51, Issue 1
  • DOI: 10.1107/S0108767394005726

A short history of SHELX
journal, December 2007

  • Sheldrick, George M.
  • Acta Crystallographica Section A Foundations of Crystallography, Vol. 64, Issue 1, p. 112-122
  • DOI: 10.1107/S0108767307043930

Projector augmented-wave method
journal, December 1994


Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set
journal, July 1996


Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set
journal, October 1996


Ab initiomolecular dynamics for liquid metals
journal, January 1993


From ultrasoft pseudopotentials to the projector augmented-wave method
journal, January 1999


Generalized Gradient Approximation Made Simple
journal, October 1996

  • Perdew, John P.; Burke, Kieron; Ernzerhof, Matthias
  • Physical Review Letters, Vol. 77, Issue 18, p. 3865-3868
  • DOI: 10.1103/PhysRevLett.77.3865

Chemical bonding in EuTGe (T=Ni, Pd, Pt) and physical properties of EuPdGe
journal, February 2007

  • Rocquefelte, Xavier; Gautier, Régis; Halet, Jean-François
  • Journal of Solid State Chemistry, Vol. 180, Issue 2
  • DOI: 10.1016/j.jssc.2006.11.013

Linear infinite cadmium chains in CaAu4Cd2 and other intermetallics with YbMo2Al4-type structure
journal, February 2013

  • Tappe, Frank; Matar, Samir F.; Schwickert, Christian
  • Monatshefte für Chemie - Chemical Monthly, Vol. 144, Issue 6
  • DOI: 10.1007/s00706-013-0932-8

Explicit, First-Principles Tight-Binding Theory
journal, December 1984


Crystal orbital Hamilton populations (COHP): energy-resolved visualization of chemical bonding in solids based on density-functional calculations
journal, August 1993

  • Dronskowski, Richard; Bloechl, Peter E.
  • The Journal of Physical Chemistry, Vol. 97, Issue 33
  • DOI: 10.1021/j100135a014

Minimal basis sets in the linear muffin-tin orbital method: Application to the diamond-structure crystals C, Si, and Ge
journal, August 1986


Gold Derivatives of Eight Rare-Earth-Metal-Rich Tellurides: Monoclinic R 7 Au 2 Te 2 and Orthorhombic R 6 AuTe 2 Types
journal, February 2012

  • Chai, Ping; Corbett, John D.
  • Inorganic Chemistry, Vol. 51, Issue 6
  • DOI: 10.1021/ic202342v

Electron Counting Rules and Electronic Structure in Tetrameric Transition-Metal (T)-Centered Rare-Earth (R) Cluster Complex Halides (X)
journal, November 2014

  • Steinberg, Simon; Bell, Thomas; Meyer, Gerd
  • Inorganic Chemistry, Vol. 54, Issue 3
  • DOI: 10.1021/ic502374y

Improved tetrahedron method for Brillouin-zone integrations
journal, June 1994


EuAg x Al 11− x with the BaCd 11 -Type Structure: Phase Width, Coloring, and Electronic Structure
journal, January 2009

  • Wang, Fei; Pearson, Karen Nordell; Miller, Gordon J.
  • Chemistry of Materials, Vol. 21, Issue 2
  • DOI: 10.1021/cm803021u

Late transition metal anions acting as p-metal elements
journal, April 2008


Electronegativity values from thermochemical data
journal, June 1961


Works referencing / citing this record:

Revealing Tendencies in the Electronic Structures of Polar Intermetallic Compounds
journal, February 2018


Revealing the Nature of Chemical Bonding in an ALn2Ag3Te5-Type Alkaline-Metal (A) Lanthanide (Ln) Silver Telluride
journal, May 2019


Controlling magnetism via transition metal exchange in the series of intermetallics Eu(T1,T2) 5 In (T = Cu, Ag, Au)
journal, January 2018

  • Smetana, Volodymyr; Mudryk, Yaroslav; Pecharsky, Vitalij K.
  • Journal of Materials Chemistry C, Vol. 6, Issue 6
  • DOI: 10.1039/c7tc04964a

Revealing Tendencies in the Electronic Structures of Polar Intermetallic Compounds
text, January 2018


Revealing the Nature of Chemical Bonding in an ALn2Ag3Te5-Type Alkaline-Metal (A) Lanthanide (Ln) Silver Telluride
text, January 2019