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Polymer hydrogels embedded with magnetic nanoparticles are a novel class of composite materials and they gained a lot of attention in the last two decades due to their interesting properties which combine the viscoelasticity of the polymeric network and the sensitivity of magnetic nanoparticles to the external magnetic field. Although γ- irradiation method is highly suitable for generation of nanoparticles (NPs) in a solution as well as for the formation of three-dimensional polymer network, i.e. hydrogels, the radiolytic syntheses of iron oxide/polymer nanocomposite gels are rarely investigated, especially in the case of one-step synthetic approaches, such as the one used in this work. The radiolytic one-step synthesis resulted in the simultaneous crosslinking of the PEO polymer and the reduction of iron (III) salt. In this work, we performed electron microscopy, XRD, SQUID (ZFC and FC, magnetization-temperature measurements), ac susceptometry and Mössbauer measurements (external magnetic field) to elucidate the structural and magnetic properties of synthesized ferrogels. The particles were identified as magnetite/maghemite and showed that they were < 5 nm in size, superparamagnetic and that there was a significant contribution of surface effects on the magnetic properties of the nanoparticles embedded in the hydrogel. Mössbauer measurements showed that the samples consist of core-shell magnetic structure and large spin canting (32-36°) on the outer layer of the particles. Furthermore, a significant contribution of spin-glass behavior and/or dipole-dipole interactions between the nanoparticles was seen from ac susceptometry and SQUID magnetometry. Acknowledgments: This work has been supported by the Croatian Science Foundation under the project UIP-2017-05-7337 (POLRADNANOP).

Superparamagnetic iron oxide nanoparticles (SPIONs) due to their unique magnetic (superparamagnetism and high saturation field) and electrical properties have applications as sensor, contrast agents, in drug delivery and for hyperthermia cancer treatments. These nanoparticles (NPs) can be modified with noble metal NPs, which combines the magnetic and biocompatible properties of SPIONs and the optical properties of noble metal NPs. In this work we used -irradiation as an attractive and ecologically friendly technique for the synthesis of magnetic NPs at room temperature. -irradiation has an advantage of inducing electrons and other reducing species homogeneously through the sample. The FeCl3 alkaline aqueous solutions were purged with N2 and irradiated with addition of 2- propanol. DEAE-dextran was used as growth and stabilizing agent of MNPs. The phase composition, stoichiometry and morphology of MNPs were controlled by adjusting γ-irradiation dose and dose rate. Doses 10-36 kGy resulted in the formation of small 4 nm spherical substoichiometric magnetite NPs, whereas at higher dose (50 kGy or more) the major phase was magnetic -FeOOH (feroxyhyte) in the form of nanodiscs, as confirmed by SEM, HRTEM, XRD and electron diffraction. The magnetic measurements revealed superparamagnetic behaviour of magnetite NPs and exceptional intrinsic room-temperature properties of -FeOOH with Curie temperature above 300 K. The reduction of Fe3+ to Fe2+ ions was determined using 1, 10-phenanthroline spectrophotometric method. Reduction proceeds fast in the beginning stage of irradiation (up to 30 kGy, 65% Fe3+ reduced), slows down and reaches 100% reduction at 75 kGy. The reducing power of Fe2+ in irradiated suspensions was explored to synthesize composite nanostructures by addition of aqueous solutions of HAuCl4 or AgNO3 in irradiated suspensions. Microstructural and morphological analysis showed that simultaneous oxidation of Fe(OH)2 and reduction of Au3+ or Ag+ resulted in the formation of composite δ-FeOOH nanodiscs decorated with spherical Au or Ag nanoparticles.

Despite a huge expansion of research on compositionally complex alloys, CCA (such as the entropy alloys, HEA and the corresponding glassy alloys) their comprehension is still limited, which is detrimental both for the design of CCAs and for their application. The broad compositional range in CCAs enables simple tuning of their properties by varying the contents of their constituent elements. Accordingly, the study of transition from CCA to conventional alloy, CA composed from the same constituents is important, both for understanding the formation of solid solutions in CCAs and for proper evaluation of their potential with respect to that of CAs. However, this transition has so far been studied systematically in only two types of alloys: isopleths of the Cantor alloy and glassy TiZrNbCuNi/Co alloys with variable Co, Ni or Cu content (Materials 14 (2021) 5824 and ref. therein). In both alloy systems the variation of a given property with composition depends sharply on the selected principal component and can be either monotonic (like that in the ideal solid solution) or non-monotonic. When the variation is non- monotonic, the maximum value of the selected property is usually outside of HEA composition range.

Magnetic polymer gels are a new promising class of nanocomposite gels with numerous potential applications as effective absorbents of toxic ions in water, in soft actuators such as artificial muscles, in tissue engineering, drug delivery, hyperthermia applications, etc. In this work, the magnetic and rheological properties of radiologically synthesized magnetic PEO/iron oxide hydrogels were systematically investigated. Magnetic PEO/iron oxide nanocomposite hydrogels were for the first time synthesized by a one-step γ-irradiation method starting from poly(ethylene oxide) (PEO) and iron(III) suspensions, followed by the simultaneous crosslinking of PEO chains and reduction of Fe(III) precursor. Magnetic hydrogels with embedded magnetite nanoparticles were obtained with 2-propanol and at high doses, as confirmed by XRD, SEM, TEM and Mössbauer spectroscopy. Rheological measurements confirmed the formation of a well-structured network. The rheological properties of the gels depended on the dose, PEO concentration and the amount of nanoparticles synthesized in the gels (initial Fe3+ content). Stronger gels with higher degree of intermolecular crosslinking were formed at higher dose and higher nanoparticle content. Magnetic iron oxide nanoparticles acted as reinforcing agents and additional crosslinkers of PEO chains facilitating gel formation in one step. All gels exhibited very good self-recoverable properties. SQUID magnetization measurements and Mössbauer spectroscopy showed that the samples exhibited superparamagnetic behavior even at very low temperatures. However, preliminary ac susceptibility measurements showed a deviation from Arrhenius' law ; the relaxation times of the composite hydrogels are unphysically small, suggesting that the particles interact with each other. Furthermore, in-field Mössbauer spectroscopy showed that the samples exhibit spin- canting phenomenon, presumably at the nanoparticle surface, forming a magnetically disordered shell with a ferrimagnetically ordered core.

Despite a huge expansion of research on compositionally complex alloys, CCA (such as the approximately equimolar, multi-component high- entropy alloys, HEA and the corresponding high- entropy glassy alloys), their basic understanding is still limited, which is detrimental both for the design of CCAs and for their application. In particular, the prediction of compositions capable of forming random solid solutions (RSSs) and the prediction of their properties is still a problem. Nevertheless, some properties of a few CCAs exceed those of conventional alloys (CA) [1].

γ-irradiation is an attractive and environmentally friendly technique for the synthesis of magnetic iron oxide nanoparticles at room temperature. In this work, deaerated alkaline aqueous suspensions of iron(III) chloride were irradiated in the presence of 2- propanol and a polymer stabilizer to synthesize magnetic iron oxide nanoparticles (MIONs). We studied the effect of different polymer stabilizers (DEAE-dextran, poly(ethylene oxide)) and the effect of γ-irradiation dose on the synthesis of MIONs. The magnetic properties of the samples were studied by SQUID magnetometry and 57Fe Mössbauer spectrometry, and their structural and morphological properties were analyzed by XRD and electron microscopy. The samples showed significantly different phase compositions, morphologies and exhibited superparamagnetic behavior even at very low temperatures, depending on the polymer and absorbed dose. In-field Mössbauer spectrometry showed that the samples exhibited spin-canting phenomenon, presumably at the nanoparticle surface. Acknowledgments: This work has been supported by the Croatian Science Foundation under the project UIP-2017-05-7337 (POLRADNANOP).

Magnetic polymer gels (ferrogels) are a new promising class of nanocomposite hydrogels, with potential application in soft actuators such as artificial muscles, in tissue engineering, drug delivery and hyperthermia applications. Although -irradiation method is highly suitable for generation of nanoparticles (NPs) in a solution as well as for the formation of three-dimensional polymer network, i.e. hydrogels, the radiolytic syntheses of iron oxide/polymer nanocomposite gels are rarely investigated, especially in the case of one-step synthetic approaches, such as the one used in this work. The radiolytic one-step synthesis resulted in the simultaneous crosslinking of the PEO polymer and the reduction of iron (III) salt (Figure 1). Electron microscopy, XRD, SQUID and Mössbauer measurements identified the particles as magnetite/maghemite and showed that they were < 5 nm in size, superparamagnetic and that there was a significant contribution of surface effects on the magnetic properties of the nanoparticles embedded in the hydrogel [1]. Acknowledgments: This work has been supported by the Croatian Science Foundation under the project UIP-2017-05-7337 (POLRADNANOP).

Using a He3 cryostat in a superconducting magnet with fields up to 16 T, superconductivity of (TiZrNbCu)1-xNix and (TiZrNbNi)1-xCux metallic glasses was studied over a broad concentration range from the high entropy alloys (HEA) region to the Ni- and Cu-rich alloys, respectively. We have observed that the upper critical fields of these alloys are Pauli limited and that the superconducting transition temperatures follow the behaviour of the dressed density of states at the Fermi level Nγ(EF), which is common in transition metals and their alloys [1]. In particular, we have shown that the electron-phonon coupling constant λe-p is proportional to the band density of the state at the Fermi level in our alloys, but also crystalline HEAs [2-4], and in other transition metal alloys. This addresses the problem of unusual superconductivity behaviour [4] which was attributed to the chemical complexity of HEAs but is shown to be inherent to transition metals. Although, minor complications do arise from combining metals of different transition series. [1] R. C. Dynes, C. M. Varma, J. Phys. F Met. Phys. 6 (7) (1976) L215-L219 [2] P. Koželj et al, Phys. Rev. Lett. 113 (10) (2014) 107001 [3] S. Vrtnik et al, J. Alloy. Compd. 695 (2017) 3530– 3540 [4] F. von Rohr et al, Proc. Natl. Acad. Sci. 113 (46) (2016) E7144–E7150

Magnetic iron oxide nanoparticles (MNPs) due to their unique magnetic and electrical properties have applications as sensor, contrast agents, in drug delivery and for hyperthermia cancer treatments. In this work we have used γ- irradiation as an attractive and ecologically friendly technique for the synthesis of magnetic nanoparticles at room temperature. γ- irradiation has an advantage of inducing electrons and other reducing species homogeneously through the sample. We have systematically studied the influence of γ- irradiation dose on the synthesis of iron oxide nanoparticles. The iron(III) chloride alkaline aqueous solutions were purged with nitrogen and g-irradiated with addition of 2-propanol. DEAE- dextran was used as growth and stabilizing agent of MNPs in suspensions. The phase composition, stoichiometry and morphology of MNPs were controlled by adjusting γ-irradiation dose and dose rate. Irradiation with doses 10 - 36 kGy resulted in the formation of very small 4 nm spherical substoichiometric magnetite NPs, whereas at higher dose (50 kGy or more) the major phase was magnetic δ-FeOOH (feroxyhyte) in the form of nanodiscs. The magnetic measurements showed superparamagnetic behaviour of magnetite NPs and exceptional intrinsic room-temperature magnetic properties of δ-FeOOH nanostructures with the Curie temperature above 300 K. The reduction of ferric (Fe3+) to ferrous (Fe2+) ions was quantitatively determined using the 1, 10-phenanthroline spectrophotometric method. The reduction proceeds fast in the beginning stages of irradiation (up to 30 kGy, ~65% Fe3+ reduced), slows down after this initial period, and reaches 100% reduction at ~75 kGy. However, ferrous ions (Fe2+) that formed upon g- irradiation of iron(III) precursor in the form of intermediate Fe(OH)2 were highly susceptible to oxidation and in the contact with air oxidized to Green Rust (formula) and further upon isolation to δ-FeOOH nanodiscs. Furthermore, the possibility to use γ- irradiation to form iron oxide/Au nanostructures was explored.

In metallic systems electronic structure determines almost all their properties. Therefore, a change in properties of multicomponent alloys on crossing from HEA to conventional alloy concentration range in the same alloy system reflects the corresponding change in ES.

The study of transition from conventional concentrated alloys to high-entropy ones composed from the same elements is apparently very important, both for understanding the formation of HEAs and for proper evaulation of their potential with respecct to that of corresponding CAs.

Iron(III) chloride deaerated alkaline aqueous colloidal solutions in the presence of 2- propanol and DEAE-dextran (diethylaminoethyl- dextran hydrochloride) were γ-irradiated with doses of 36 and 130 kGy. The dose rates were ~7 and ~31 kGy h-1. Substoichiometric magnetite nanoparticles ~4-5 nm in size formed at a dose of 36 kGy. The dose rate had an effect on the stoichiometry of the formed magnetite. At a dose of 130 kGy and the lower dose rate, the anisotropic d-FeOOH magnetic discs with a diameter of ~256 nm and thickness of ~40 nm self-assembled. At a dose of 130 kGy and the higher dose rate, the rolled rod-like d-FeOOH magnetic nanoparticles were formed having the diffraction patterns characteristic of tubular structures. The magnetic measurements showed exceptional intrinsic room-temperature magnetic properties of both d-FeOOH nanostructures with the Curie temperature above 300 K. In order to ascertain the formation of Fe(II) intermediate products prior to their oxidation, the γ- irradiated samples were isolated by admixing glycerol. The amounts of Fe(II) in glycerol- isolated solid samples were 9.9 % and 86.0 %, as determined by Mössbauer spectroscopy at doses of 36 and 130 kGy, respectively. Carbonate Green Rust I, GR(CO32-), and Fe(OH)2 intermediate phases were confirmed by XRD and Mössbauer spectroscopy.

The formation of transition metal compounds (TC) in selected devitrified high-entropy (HE) and conventional metallic glasses (MG) has been studied by using X-ray diffraction (XRD) and magnetic susceptibility (χ) measurements. The alloys selected were Al0.5TiZrPdCuNi [1], (TiZrNbL)1-xMx (L = Cu, Ni ; M = Fe, Co, Ni, Cu) [2] HEMGs, as well as conventional binary and ternary MGs containing early (TE) and late (TL) transition metals, such as the Ti, Zr, Hf – L [3] and Zr-Cu-Al alloys. Such study provides a comparison between the crystallization patterns in TE-TL HEMGs and these in conventional MGs with the same constituents, which can help to understand the differences in glass forming ability (GFA) between HEMGs and conventional MGs [2, 3]. The measurements of χ on both as-cast and crystallized alloys provide an insight into the changes of electronic structure (ES) accompanying transition from amorphous to crystalline (TCs) state, which seem to determine GFA of TE-TL alloys [3]. Further, the values of χ for crystallized alloys, χc, enable in principle the determination of χc values corresponding to particular TCs. These χc (TC) values in addition to giving an insight into contribution of given TC to ES also enable the determination of the fractions of TCs in a given alloy. This is important for a quantitative analysis of the phase contents in alloys in which the crystalline texture make the determination of phase contents from XRD less accurate. Wherever possible we compare and combine our data with the results from literature. _____________________________________________ ∗ This work was supported by UNAM-DGAPA-PAPIIT project No. IN101016 and Osijek University project IZIP2016-3. † [1] A. Takeuchi et al, Mater. Trans. 54 (2013) 776 ; [2] K. Biljaković et al., J. Alloys Compd. 695 (2017) 2661 and I. A. Figueroa et al., submitted to J. Alloys Compd. ; [3] R. Ristić et al., EPL 114 (2016) 17006 and E. Babić et al., submitted to Phil. Mag..

Rapidly cooled atomic and molecular liquids can bypass crystallization and vitrify. While network bonding in silica and chain entanglement in polymers seem plausible mechanisms for inhibiting their crystallization, the corresponding mechanism for metallic systems is less clear. When molten alloy is cooled, the formation of metallic glass (MG) usually competes with that of intermetallic compounds (IC): thus similar free energies (G) of MG and competing IC(s) facilitate vitrification. At low temperatures G is dominated with internal energy which in metallic systems strongly depends on electronic structure (ES). Thus small differences in ES between MG and competing IC(s) promote vitrification, as observed in several binary and ternary transition metal (TM) alloy systems. This correlation seems applicable to all TM alloys irrespective on their number of alloying components (thus also to high-entropy alloys) and provides a simple way to select compositions with high glass forming ability. This work was supported by UNAM-DGAPA-PAPIIT project No.IN101016 and Osijek University project IZIP2016-3

On cooling of molten alloy the formation of metallic glass (MG) competes with that of intermetallic compounds (TC). This competition determines glass forming ability (GFA) of a given alloy and in binary alloys GFA can be expressed in terms of the formation enthalpies of MG and competing TCs [1]. More recently we have shown that a similar electronic structure, ES, (represented by the density of states (DoS) at the Fermi level, N(EF)) of competing TCs to that of MG enhances GFA in Cu-Hf, Zr alloys [2]. In particular, we found that small difference between the N(EF)-dependent properties (such as magnetic susceptibility (χ) and Sommerfeld coefficient (γ)) of as-cast and crystallized MGs reflects an enhanced GFA. Combining our and literature results for N(EF) and χ we show here that this correlation holds in all binary (Cu, Ni-Ti, Zr, Hf) and ternary (Cu-Hf-Ti, Cu-Zr-Al) alloys of early (TE) and late (TL) transition metals for which there exist relevant data. The correlation between ES and GFA shows up the best in Cu-Zr and NiZr2 alloys in which the data for change in N(EF) upon crystallization exist. The applicability of this correlation (GFA criterion) to all TE-TL alloys is supported by photoemission studies and low temperature specific heat measurements [3] which show similar composition dependencies irrespective of the number of components in the alloy. _____________________________________________ ∗ This work was supported by UNAM-DGAPA-PAPIIT project No. IN101016 and Osijek University project IZIP2016-3. † [1] R. Ristić et al., J. Alloys and Compd. 621 (2015) 136 ; [2] K. Biljaković et al., J. Alloys Compd. 695 (2017) 2661 ; [3] R. Ristić et al. EPL , 114 (2016) 17006.

In order to study Kondo ferromagnetism, we have investigated the CexLa1-xPt, and CexY1-xPt alloy systems in the temperature range from 1.8 K to 320 K. While CexY1-xPt show considerable hybridization and, therewith, Kondo effect, in CexLa1-xPt hybridization very weak. By the resistivity measurements, we determined the energetic specter of the 4f level of the Ce3+ ion split by the crystal electrical field (CEF): a doublet and a quasiquartet at 120 K. The magnetic contribution to the resistivity, ρmag, of CexLa1-xPt is nicely scaled to concentration. The ρmag of CexY1-xPt is successfully described by Cornut – Coqblin theory. The minimum in the thermopower which one usually ascribes to Kondo minimum, does not correspond to Kondo effect ; rather to CEF. The dc susceptibility can be described by the Curie-Weiss law down to about 100 K and also above in the vicinity phase transition. The Curie-Weiss constant at high temperature θp, is negative indicating that the interaction between the spin of the Ce ion and conducting electron is antiferromagnetic one. At low temperatures, θC is positive indicating the transition into ferromagetic ordered state. The effective magnetic moment per Ce ion, µef, at the higher temperatures is the same for all alloys of CexLa1-xPt and is close to the theoretical value of the isolated Ce3+ ion, µ = 2.54µB, indicating the hybridization is very weak and, and, consequently, Kondo effects are weak. At low temperatures, µef ≈ 1.5 µB is also the same for all alloys. On contrary, µef of CexY1-xPt at high as well at low temperatures strongly depend on the Ce content, x. These observations confirm the main important conclusions inferred from the investigations of the transport properties of these alloy systems. Although La and Y are nonmagnetic, they have a strong influence on the different magnetic properties of these two systems, but, interestingly enough, they have no considerable effect on the Curie temperature, TC. The TC(x) linearly depends on x and it is about the same for both systems. We show that these systems cannot be considered within Doniach’s diagram. The ac susceptibility shows in CexY1-xPt (x < 1) double-peak structure in the vicinity of the phase transition, TC, which is determined by the resistivity measurements. The peak at lower temperatures corresponds to one- peak structure in CexLa1-xPt reflecting TC. The peak at high temperatures reveal the processes which may be treated as an entrance CexLa1-xPt in a new phase of CexY1-xPt. It is stretched within less than 1 K above TC and it is within the Griffiths phase but has quite different underlying physics. This phase is characterized with long range ordered ferromagnetic fluctuations which do not allow spin fluctuations. i.e., Kondo interaction and thus the Ce3+ is in the stable state just it is in CexLa1-xPt. This explains why TC(x) is the same for both systems and why RKKY interaction is not responsible for the ferromagnetism leading us to the conclusion that direct exchange interaction establishes ferromagnetism in these alloy systems. We believe that the same process takes place in all truly Kondo ferromagnetics. However, it is difficult to be noticed because it takes place in a very narrow temperature interval above TC. In addition, we noticed this process because we investigated two similar alloy systems where in one them, CexLa1-xPt, hybridization is very weak while in the other one, CexY1-xPt, is very strong.

Polinuklearni kompleksi od posebnog su zanimanja za znanstvenu zajednicu radi temeljnog istraživanja međudjelovanja izmjene magnetskih centara i radi mogućih primjena kao osnovnih građevnih jedinica molekulskih magneta. Sinteza novih kompleksa uznapredovala je na način da je moguće dizajnirati spojeve željene strukture. Poseban je izazov proučavati vezu između strukture i magnetskih svojstava. U ovom radu sintetiziran je niz od 13 novih tetranuklearnih kompleksa Ni(II) kubana, [Ni4L4(CnH2n+1OH) (CmH2m+1OH)] (n, m=1, 2, 3, 4, 5 ; L je organski ligand) te je istraživan utjecaj finih strukturnih promjena na magnetsko ponašanje. Kod nekih od kompleksa opažen je neobično visoki maksimum krivulje xT(T) (preko 20 emuK/molOe). Magnetsko ponašanje modelirano je spinskim hamiltonijanom koji uključuje međudjelovanje izmjene, cijepanje energijskih razina bez prisutnosti polja (ZFS) i međudjelovanje molekula. Numeričkom prilagodbom i simulacijama utvrđeno je da opaženi visoki maksimumi krivulja xT(T) potječu od osnog doprinosa ZFS te su dobiveni i drugi parametri magnetskih međudjelovanja. Pokazane su korelacije između parametara magnetskih međudjelovanja i tri strukturna parametra: prosječnog Ni1-O-Ni2 kuta, prosječnog kuta između O-Ni-O ravnina i prosječnog kuta između O-Ni1-O ravnine i Ni1-Ni2 vektora. Utvrđeno je da se finom promjenom strukture ugradnjom različitih liganada može utjecati na parametre magnetskih međudjelovanja i promjenu osnovnog stanja.[1] [1] Ovaj rad financiran je projektom Hrvatske zaklade za znanost (UIP-2014-09-8276)

Magnetoelectric multiferroics are materials in which both the magnetic and electric orders appear, that becomes especially interesting if coupling between them is present and/or the orders are established simultaneously. Such materials are under intensive investigation since mechanisms of these effects are not fully understood, and the application of such materials in sensors, memory elements, photovoltaics, nano-electronics is expected. Here we present the installed upgrades of the experimental setups which make possible to apply the electric field and measure its influence on the magnetization using commercial magnetometer, and also to measure electric properties of the material in magnetic field. This allows to investigate the magnetoelectric effects together with their magnetic and electric states. Within the project we are studying two general classes of materials: mixed metal oxides (like CaCr2O4, CrNbO4, BiFeO3, birnessite and double perovskites) and metal-organic complexes (including 3D coordination polymers, layered structures of magnetic and polar components, coupled magnetic chains and 0D objects). Some novel magnetoelectric results will be shortly presented. In order to better understand behaviour of the synthesized compounds, including their ground magnetic and polar states, theoretical quantum calculations on the studied structures are undertaken. In this way, we complete the research cycle from synthesis and structure determination, to full magnetic and electric investigation and theoretical calculation. Doctoral student and postdoc are associated in the project. Installation research project “Multiferroic and magnetoelectric systems” (FerMaEl) is supported by the Croatian Science Foundation under the grant UIP-2014-09-8276. (http://www.phy.pmf.unizg.hr/~dpajic/FerMaEl/)

Recently we reported a correlation between the change in magnetic susceptibility upon crystallization of Cu-Zr, Hf metallic glasses and glass forming ability (GFA) in these alloys [1]. In particular we have shown that a small difference in magnetic susceptibilities of corresponding amorphous and crystalline alloys reflects high GFA (represented by high value of the reduced glass transition temperature Trg=Tg/Tl , where Tg and Tl are the glass transition and liquidus temperatures, respectively). Further, we have shown that this correlation stems from similar electronic structures, ES (represented by the electronic density of states at the Fermi level, N(EF)) of amorphous and corresponding crystalline alloy [1, 2]. Here we extended a study of this correlation by investigating the magnetic susceptibilities over a broad composition range in several Ti-Cu, Zr-Cu and Zr-Ni alloys. In particular we studied a change of magnetic susceptibility upon crystallization in five Ti-Cu and four selected Zr-Cu and Zr-Ni metallic glasses. Actual compositions of Zr-Cu and Zr-Ni alloys were selected to complete and verify the literature results for these alloy systems [3, 4]. The methods employed for magnetic susceptibility measurements and crystallization of studied alloys were the same as in our previous report [1]. The fully crystalline final state of all our alloys was verified by x-ray diffraction patterns. An important novel feature of a present study is that we use the experimental critical casting thickness dc which is directly related to GFA to describe the variation of GFA with composition in Ti-Cu, Hf-Cu and Zr-Cu alloys. (Since for Zr-Ni alloys dc data do not exist we described the variation of GFA in these alloys by using the empirical GFA criteria such as Trg.) For all four studied alloy systems, very good correlation between dc and / or other criteria for high GFA and the change in magnetic susceptibility upon crystallization of metallic glasses has been obtained. The correlation between ES and GFA in these alloys also showed up the best in Zr-Cu alloys (where also the data for the change in N(EF) upon crystallization are available [2]) and in Zr2Ni alloy which exhibits a local maximum in GFA due to virtually no difference between N(EF) of metallic glass and corresponding intermetallic compound. The applicability of this criterion for GFA (which provides a simple way to select the composition with high GFA) to other metal-metal metallic glasses (including ternary and multicomponent bulk metallic glasses) is briefly discussed. 1. R. Ristić et al, EPL 114, 17006 (2016). 2. P. Garoche and J. Bigot, Phys. Rev B 28, 6886 (1983). 3. Z. Altounian, T. Guo-Hua and J. O. Strom- Olsen, J. Appl. Phys. 53, 4755 (1982). 4. Z. Altounian, T. Guo-Hua and J. O. Strom- Olsen, J. Appl. Phys. 54, 3111 (1983).