The main field of interest in the Group is MAGNETISM, in particular:

  • Molecular magnetism.
  • Geometrically frustrated magnetic systems (pyrochlores, garnets)
  • Magnetic and electronic properties of rare-earth intermetallic and oxide phases, especially Quantum phase transitions

We study magnetic properties of molecular compounds, especially those based on cyanide bridges -C-N- between 3d, 4d, 5d and 4f metal ions. In particular we focus on behaviour of single chain magnets with slow relaxation of magnetization observed at low temperatures, photomagnetism, and solvent-sensitivity of such compounds.

These projects are realized in close collaboration with chemists, particulary from groups of prof. B. Sieklucka (Kraków) and prof. C. Näther (Kiel).

  • helium recovery system and liquifier

Low temperature magnetic, transport and calorimetric measurements

  • Quantum Design MPMS-5XL squid magnetometer
  • QD PPMS, 9T with He3 cooling, magneto-transport and specific heat measurements down to 0.4 K, and in field up to 9 T

Hyperfine interaction measurements

  • Mossbauer effect measurements with 151Eu and 57Fe and 99Ru
  • Perturbed angular correlation with 99Ru and 172Yb (no longer)

Sample preparation

  • high temperature ovens for samples sintering up to 1500 degC
  • Simens D500 x-ray diffractometer
  • 2017

S. Suckert, M. Rams, L.S. Germann, D.M. Cegiełka, R.E. Dinnebier, C. Näther.
Thermal transformation of a zero-dimensional thiocyanate precursor into a ferromagnetic three-dimensional coordination network via a layered intermediate
Cryst.Growth.Design. (2017) doi: 10.1021/acs.cgd.7b00655

M. Arczynski, M. Rams, J. Stanek, M. Fitta, B. Sieklucka, K.R. Dunbar, D. Pinkowicz.
A Family of Octahedral Magnetic Molecules Based on [NbIV(CN)8]4–
Inorg. Chem. 56 (2017) 4021-4027

M. Rams, Z. Tomkowicz, M. Böhme, W. Plass, S. Suckert, J. Werner, I. Jess, C. Näther.
Influence of the Metal Coordination and the co-Ligand on the Magnetic Properties of 1D Co(NCS)2 Coordination Polymers.
Phys. Chem. Chem. Phys. 19 (2017) 3232-3243

B. Nowicka, M. Heczko, M. Rams, M. Reczyński, B. Gaweł, W. Nitek, B. Sieklucka.
Solvatomagnetic studies of the cyano-bridged bimetallic chains based on [Mn(cyclam)]3+ and hexacyanometallates.
Eur. J. Inorg. Chem 2017 (2017) 99-106

S. Suckert, M. Rams, M.M. Rams, C. Näther.
Reversible and topotactic solvent removal in magnetic Ni(NCS)2 coordination polymer
Inorg. Chem., (2017) doi:

S. Chorazy, M. Rams, J. Wang, B. Sieklucka, S. Ohkoshi.
Octahedral Yb(III) complexes embedded in [CoIII(CN)6]-bridged coordination chains: combining sensitized near-infrared fluorescence with slow magnetic relaxation

M. Rams, M. Bohme, V. Kataev, Y. Krupskaya, B. Buchner, W. Plass, T. Neumann, I. Jess, Z. Tomkowicz, C. Näther.
Static and dynamic magnetic properties of the ferromagnetic coordination polymer [Co(NCS)2(py)2]n

 
  • 2016

S. Chorazy, J. Stanek, W. Nogas, A.M. Majcher, M. Rams, M. Kozieł, E. Juszyńska-Gałązka, K. Nakabayashi, S. Ohkoshi, B. Sieklucka, R. Podgajny.
Tuning of charge transfer assisted phase transition and slow magnetic relaxation functionalities in Fe9-xCox[W(CN)8]6 (x=0-9) molecular solid solution.
J. Am. Chem. Soc. 138 (2016) 1635

S. Chorazy, M. Rams, A. Hoczek, B. Czarnecki, B. Sieklucka, S. Ohkoshi, R. Podgajny.
Structural anisotropy of cyanido-bridged {CoII9WV6} Single-Molecule Magnets induced by bidentate ligands: towards the rational enhancement of energy barrier.
Chem. Commun. 52 (2016) 4772.

S. Suckert, M. Rams, M. Böhme, L.S. Germann, R.E. Dinnebier, W. Plass, J. Werner, C. Näther.
Synthesis, structures, magnetic, and theoretical investigations of layered Co and Ni thiocyanate coordination polymers.
Dalton Trans. 45 (2016) 18190

S. Chorazy, M. Rams, K. Nakabayashi, B. Sieklucka, S. Ohkoshi.
White light emissive DyIII single-molecule magnets sensitized by diamagnetic [CoIII(CN)6]3- linkers.
Chem-Eur.J. 22 (2016) 7371.

B. Nowicka, M. Reczyński, M. Rams, T. Wasiutyński, W. Nitek, B. Sieklucka.
Ligand dependent topology and spontaneous resolution in high-spin cyano-bridged Ni3W2 clusters.
Dalton Trans. 45 (2016) 12423.

B. Nowicka, M. Heczko, M. Reczyński, M. Rams, B. Gaweł, W. Nitek, B. Sieklucka.
Exploration of a new building block for the construction of cyano-bridged solvatomagnetic assemblies: [Ni(cyclam)]3+.
CrystEngComm 18 (2016) 7011.

  • 2015

D. Pinkowicz, M. Rams, M. Misek, K.V. Kamenev, H. Tomkowiak, A. Katrusiak, B. Sieklucka.
Enforcing Multifunctionality: A Pressure-Induced Spin-Crossover Photomagnet.
J. Am. Chem. Soc. 137 (2015) 8795, open acces PDF

S. Chorazy, R. Podgajny, K. Nakabayashi, J. Stanek, M. Rams, B. Sieklucka, S-i. Ohkoshi.
FeII spin-crossover phenomenon in the pentadecanuclear {Fe9[Re(CN)8]6} spherical cluster.
Angewandte Chemie Inter. Ed. 54, 5093-5097 (2015)

O. Stefanczyk, A.M. Majcher, M. Rams, W. Nitek, C. Mathoniere, B. Sieklucka.
Photo-induced magnetic properties of the [CuII(bapa)]2[MoIV(CN)8]7H2O molecular ribbon.
J. Mater. Chem. C, 2015, 3, 8712

B. Nowicka, M. Reczyński, M. Rams, W. Nitek, J. Żukrowski, C. Kapusta, B. Sieklucka.
Hydration-switchable charge transfer in the first bimetallic assembly based on the [Ni(cyclam)]3+ – magnetic CN-bridged chain {(H3O)[NiIII(cyclam)][FeII(CN)6]·5H2O}n.
Chem. Comm. 51 (2015) 11485

J. Werner, M. Rams, Z. Tomkowicz, T. Runčevski, R.E. Dinnebier, S. Suckert, C. Näther.
Thermodynamically metastable thiocyanato coordination polymer that shows slow relaxations of the magnetization.
Inorg. Chem. 54, 2893–2901 (2015)

J. Werner, Z. Tomkowicz, M. Rams, S.G. Ebbinghaus, T. Neumann, C. Näther.
Synthesis, structure and properties of [Co(NCS)2(4-(4-chlorobenzyl)pyridine)2]n, that shows slow magnetic relaxations and a metamagnetic transition.
Dalton Trans. 44, 14149 (2015)

M. Wasniowska, M. Sikora, M. Dobrzanski, T. Eelbo, M.M. Soares, M. Rams, I. Miotkowski, R. Wiesendanger, R. Berndt, Z. Kakol, A. Kozlowski.
Investigating the differences between Co adatoms states on surfaces of selected bismuth chalcogenides.
Physical Review B 92 (2015) 115412.

O. Stefanczyk, A.M. Majcher, M.Rams, W. Nitek, C. Mathoniere, B. Sieklucka.
Linking magnetic M-II-[M-V[CN)(8)] chains into 2D inorganic-organic hybrid materials.
CrystEngComm 17 (2015) 4533.

B. Nowicka, M. Reczynski, M. Rams, W. Nitek, M. Koziel, B. Sieklucka.
Larger pores and higher T-c: {[Ni(cyclam)](3)[W(CN)(8)](2)center dot solv}(n) - a new member of the largest family of pseudo-polymorphic isomers among octacyanometallate-based assemblies.
CrystEngComm 17 (2015) 3526

S. Chorazy, R. Podgajny, W. Nogas, S. Buda, W. Nitek, J. Mlynarski, M. Rams, M. Kozieł, E. Juszyńska-Gałązka, V. Vieru, L. Chibotaru, B. Sieklucka.
Optical activity and dehydration-driven switching of magnetic properties in enantiopure cyanido-bridged CoII3WV2 trigonal bipyramids
Inorg. Chem. 54 (2015) 5784.

S. Chorąży, M. Reczyński, R. Podgajny, W. Nogaś, S. Buda, M.Rams, W.Nitek, B.Nowicka, J.Młynarski, S.Ohkoshi, B.Sieklucka.
Implementation of chirality into high-spin ferromagnetic CoII9WV6 and NiII9WV6 cyanido-bridged clusters.
Crystal Growth & Design 15 (2015) 3573

I. Misztalewska, A.Z. Wilczewska, O. Wojtasik, K.H. Markiewicz, P.Kuchlewski, A.M. Majcher.
New acetylacetone-polymer modified nanoparticles as magnetically separable complexing agents.
RSC Advances 5 (2015) 100281

B. Cristóvão, B. Miroslaw, J. Kłak, M. Rams.
Carbonato-bridged heteronuclear Ni2IILn2III (Ln=Tb, Dy, Ho, Er, Tm, Yb, Lu) complexes synthesized by fixation of atmospheric CO2 – structural and magnetic studies.
Polyhedron 85, 697-704 (2015)

  • 2014

E. V. Peresypkina, A. M. Majcher, M. Rams, K. E. Vostrikova.
A single chain magnet involving hexacyanoosmate.
Chem. Commun. 50, 7150–7153 (2014)

M. Rams, E.V. Peresypkina, V.S. Mironov, W. Wernsdorfer, K.E. Vostrikova.
Magnetic relaxation of 1D coordination polymers (X)2[Mn(acacen)Fe(CN)6], X = Ph4P+, Et4N+.
Inorg. Chem. 53, 10291–10300 (2014)

O. Stefanczyk, M. Rams, A. M. Majcher, C. Mathoniere, B. Sieklucka.
Chiral (LH)(2)L2Cu3 trinuclear paramagnetic nodes in octacyanidometalate-bridged helical chains.
Inorg. Chem. 53, 3874–3879 (2014)

D. Pinkowicz, Z. Li, P. Pietrzyk, M. Rams.
New thiadiazole dioxide bridging ligand with a stable radical form for the construction of magnetic coordination chains.
Crystal Growth Design 14, 4878–4881 (2014)

S. Chorazy, R. Podgajny, W. Nogas, W. Nitek, M. Koziel, M. Rams, E. Juszynska-Galazka, J. Zukrowski, C. Kapusta, K. Nakabayashi, T. Fujimoto, S. Ohkoshi, B. Sieklucka.
Charge transfer phase transition with reversed thermal hysteresis loop in the mixed-valence Fe-9[W(CN)(8)](6) xMeOH cluster.
Chem. Commun. 50, 3484–3487 (2014)

J.Werner, M. Rams, Z. Tomkowicz, C. Näther.
A Co(II) thiocyanato coordination polymer with 4-(3-phenylpropyl)pyridine: the influence of the co-ligand on the magnetic properties.
Dalton Trans. 43, 17333–17342 (2014)

S. Woehlert, Z. Tomkowicz, M. Rams, S.G. Ebbinghaus, L. Fink, M.U. Schmidt, C. Näther.
Influence of the co-ligand on the magnetic and relaxation properties of layered cobalt(II) thiocyanato coordination polymers.
Inorg. Chem. 53, 8298–8310 (2014)

R. Podgajny, D. Pinkowicz, B. Czarnecki, M. Kozieł, S. Chorazy, M. Wis, W. Nitek, M. Rams, Sieklucka B.
Role of pyrazine-N,N'-dioxide in [W(CN)8]n- -based hybrid networks: anion-pi interactions.
Crystal Growth Design 14, 4030–4040 (2014)

A.M. Majcher, K. Rode, J.M.D. Coey, P. Stamenov,
Magnetic, transport, and structural properties of SrRuO3 thin films
J. Appl. Phys. 115 (2014) 17C735

  • 2013

S. Woehlert, T. Fic, Z. Tomkowicz, S.G. Ebbinghaus, M. Rams, W. Haase, C. Näther.
Structural and magnetic studies of a new Co(II) thiocyanato coordination polymer showing slow magnetic relaxations and a metamagnetic transition.
Inorg. Chem. 52, 12947–12957 (2013)

S. Chorazy, R. Podgajny, W. Nitek, M. Rams, S. Ohkoshi, B. Sieklucka.
Supramolecular chains and coordination nanowires constructed of high-spin (Co9WV6)-WII Clusters and 4,4'-bpdo Linkers.
Cryst. Growth & Design 13, 3036–3045 (2013)

S. Chorazy, R. Podgajny, W. Nitek, T. Fic, E. Goerlich, M. Rams, B. Sieklucka.
Natural and magnetic optical activity of 2-D chiral cyanido-bridged Mn-II-Nb-IV molecular ferrimagnets.
Chem. Commun. 49, 6731–6733 (2013)

S. Wohlert, M. Wriedt, T. Fic, Z. Tomkowicz, W. Haase, C. Näther.
Synthesis, Crystal Structure, and Magnetic Properties of the Coordination Polymer [Fe(NCS)(2)(1,2-bis(4-pyridyl)-ethylene)](n) Showing a Two Step Metamagnetic Transition.
Inorg. Chem. 52, 1061 (2013)

M. Mlynarczyk, K. Szot, U. Poppe, U. Breuer, S. Mi, B. Psiuk, E.A. Goerlich, K. Tomala, R. Waser.
Structural stratification of Sr1-xCaxRuO3 thin films: Influence of aging process.
Phys. Stat. Sol. A 210, 1862 (2013)

R. Podgajny, S. Chorazy, W. Nitek, M. Rams, A.M. Majcher, B. Marszałek, J. Zukrowski, C. Kapusta, B. Sieklucka.
Co–NC–W and Fe–NC–W Electron-Transfer Channels for Thermal Bistability in Trimetallic Fe6Co3[W(CN)8]6 Cyanido-Bridged Cluster.
Angewandte Chemie Inter. Ed. 52, 896–900 (2013)

S. Chorazy, R. Podgajny, A.M. Majcher, W. Nitek, M. Rams, E.A. Suturina, L. Ungur, L.F. Chibotaru, B. Sieklucka.
Magnetic anisotropy of CoII–WV ferromagnet: single crystal and ab initio study.
CrystEngComm 15, 2378 (2013)

O. Stefanczyk, A.M. Majcher, M. Rams, W. Nitek, M. Koziel, W. Lasocha, B. Sieklucka.
Incorporation of guanidinium ions between CuII-[MV (CN)8]3− double layers magnetic system.
Dalton Trans. 42, 5042 (2013)

  • 2012 (selected)

Z. Tomkowicz, M. Rams, M. Balanda, S. Foro, H. Nojiri, Y. Krupskaya, V. Kataev, B. Buechner, S. K. Nayak, J. V. Yakhmi, W. Haase.
Slow Magnetic Relaxations in Manganese(III) Tetra(meta-fluorophenyl)porphyrin-tetracyanoethenide. Comparison with the Relative Single Chain Magnet ortho Compound.
Inorg. Chem. 51, 9983–9994 (2012)

Z. Tomkowicz, S. Ostrovsky, S. Foro, V. Calvo-Perez, W. Haase.
Magnetooptical and structural investigations of five dimeric cobalt(II) complexes mimicking metalloenzyme active sites.
Inorg. Chem. 51, 6046 (2012)

D. Pinkowicz, M. Rams, W. Nitek, B. Czarnecki, B. Sieklucka.
Evidence for magnetic anisotropy of [Nb-IV(CN)(8)](4-) in a pillared-layered Mn2Nb framework showing spinflop transition.
Chem. Commun. 48, 8323–8325 (2012)

B. Nowicka, K. Stadnicka, W. Nitek, M. Rams, B. Sieklucka.
Geometrical isomerism in pentadecanuclear high-spin Ni9W6 clusters with symmetrical bidentate ligands detected.
CrystEngComm 20, 6559–6564 (2012)

O. Stefanczyk, R. Podgajny, T. Korzeniak, M. Rams, M. Koziel, W. Lasocha, D. Zajac, B. Sieklucka.
X-ray absorption spectroscopy study of novel inorganic-organic hybrid ferromagnetic Cu-pyz-[M(CN)8]3- assemblies.
Inorg. Chem. 51, 11722–9 (2012)

W.L. Boncher, E.A. Goerlich, K. Tomala, J.L. Bitter, S. Stoll.
Valence and magnetic investigations of alkali metal-doped europium sulfide.
Chem. Mater. 24, 4390 (2012)

  • 2008-2011 (selected)

D. Pinkowicz, R. Podgajny, W. Nitek, M. Rams, A.M. Majcher, T. Nuida, S. Ohkoshi, B. Sieklucka.
Multifunctional magnetic molecular {[MII(urea)2(H2O)]2 [NbIV (CN)8]}n system: magnetization-induced SHG in the chiral polymorph.
Chem. Mater. 23, 21–31 (2011)

M. Rams, A. Zarzycki, A. Pikul, K. Tomala.
Magnetic order and crystal field in Dy2Ru2O7 and Yb2Ru2O7.
J. Magn. Magn. Mater. 323, 1490–1494 (2011).

G. Schwarz, Y. Bodenthin, Z. Tomkowicz, W. Haase, T. Geue, J. Kohlbrecher, U. Pietsch, D.G. Kurth.
Tuning the structure and the magnetic properties of metallo-supramolecular polyelectrolyte-amphiphile complexes.
J. Amer. Chem. Soc. 133, 547 (2011)

Z. Tomkowicz, S. Ostrovsky, H. Mueller-Bunz, A. J. Hussein Eltmimi, M. Rams, D. A. Brown, W. Haase.
Extended triple-bridged Ni(II)- and Co(II)-hydroxamate trinuclear complexes: Synthesis, crystal structures, and magnetic properties.
Inorg. Chem. 47, 6956–6963 (2008).

M. Rams, M. Kruzel, A. Zarzycki, K. Królas, K. Tomala.
Orbital ordering in Ca2RuO4 investigated by 99Ru perturbed angular correlation.
Phys. Rev. B 80, 045119 (2009).

M. Rams, R. Kmiec, M. Kruzel, Z. Swiatkowska, J. Gurgul, K. Królas, K. Tomala.
99Ru perturbed angular correlation and Mossbauer effect investigations of SrRuO3 and CaRuO3.
J. Alloys Compounds 471, 5–10 (2009).