Structural ordering and magnetic properties of arc-melted FeGa alloys

In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 1 S uc u al o de ing and magne ic p ope ies o a c-mel ed FeGa alloys J.M. Bo ego, J.S. Blázquez, C.F. Conde and A. Conde Depa amen o de Física de la Ma e ia Condensada, Ins i u o de Ciencia de Ma e iales, C.S.I.C., Uni e sidad de Se illa, P.O. Box 1065, 41080 Se illa, Spain S. Ro h Leibniz Ins i u ü Me allische We ks o e, IFW D esden, Pos ach 270016, D-01171 D esden, Ge many Abs ac X- ay di ac ion, Mössbaue spec ome y and magne ic p ope ies ha e been pe o med on FeGa a c-mel ed bina y alloys in o de o s udy he composi ional dependence o he s uc u al o de ing and magne ic p ope ies o hese alloys. The a e age magne ic hype ine ield a 300 K dec eases wi h inc easing Ga con en as does he a e age magne ic momen pe Fe a om and a linea dependence be ween bo h quan i ies is ound o Ga con en up o 20 a . %. The subs i u ion o Fe by Ga a oms inc eases he la ice pa ame e and causes a change in he o de o he c ys al s uc u e ha has been modelled using a binomial dis ibu ion me hod. The e ec o Ga a oms as nea neighbou s o Fe on he a e age magne ic hype ine ield is e alua ed. Keywo ds: A-Magne ic in e me allics, B-Magne ic p ope ies, B-O de /diso de ans o ma ions, F-Mössbaue spec oscopy In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 2 1. In oduc ion FeGa alloys ha e a ac ed g ea a en ion in he las ew yea s due o hei supe io magne os ic i e p ope ies a low sa u a ion ield [1-4]. This quali y associa ed wi h hei high mechanical s engh, good duc ili y, negligible magne ic hys e esis and low cos [5] makes hese ma e ials e y p omising o senso and ac ua o applica ions. Recen in es iga ions include he s udy o he in luence o he he mal his o y and he s uc u al o de ing on hei magne os ic ion [6,7], he phase equilib ia and s abili y o o de ed bcc phases in he Fe- ich po ion o he FeGa sys em [8] and he s uc u al ans o ma ions in quenched FeGa alloys [9]. Mo eo e , ecen ly i was ound ha he addi ion o Cu o Fe65.5C 4Mo4Ga4P12C5B5.5 amo phous alloy p oduces a nanoc ys alline mic os uc u e consis en o FeGa nanoc ys als embedded in an amo phous ma ix [10]. These nanoc ys alline alloys a e in e es ing since hey would combine a la ge glass- o ming abili y wi h good so magne ic p ope ies. Howe e , a Mössbaue s udy o he FeGa alloy se ies is s ill missing. The impo ance o his s udy is double. On one hand, s uc u e de e mina ion o FeGa alloys by X- ay di ac ion is oublesome due o he simila i y in he a omic sca e ing ac o s o Fe and Ga a oms which esul s in supe la ice e lec ions o e y low in ensi y. Fo example, he in ensi y o he s onges supe la ice e lec ion associa ed wi h DO3 long- ange o de is calcula ed o be only 0.6% o he s onges p ima y e lec ion. Mössbaue spec ome y, as a sho ange o de sensi i e echnique, does allow dis inguishing be ween o de ed and diso de ed a omic s uc u es. Fo nanoc ys alline alloys and due o he complexi y o hei magne ic hype ine s uc u e, he cha ac e iza ion o he hype ine pa ame e s o FeGa c ys als becomes an essen ial in o ma ion. In he p esen wo k, a c-mel ed polyc ys alline Fe100-yGay (y=5, 10, 20 and 25) alloys we e p epa ed in o de o s udy a ia ions in he a omic sho ange o de a oom In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 3 empe a u e wi h subs i u ion o Fe by Ga. A local model based on a binomial dis ibu ion me hod [11] was used in o de o co ela e he magne ic hype ine pa ame e s wi h he s uc u al o de ing o hese alloys. The in luence o Ga subs i u ion o Fe on he la ice pa ame e , sa u a ion magne iza ion, magne ic momen and Cu ie empe a u e o hese alloys is also epo ed. The in e es o his s udy is ocused in demons a ing ha Mössbaue echnique is able o supply de ailed quan i a i e da a o he s uc u al o de ing o such sys ems as Fe-Ga bina y alloy whe e con en ional X- ay di ac ion echniques can no esol e an o de ed s uc u e due o he simila i y be ween he sca e ing ac o s o i s cons i uen s. 2. Expe imen al Fe100-yGay (y = 5, 10, 20 and 25 a . %) alloys we e p epa ed by a c-mel ing om pu e Fe (99.95%) and Ga (99.999%) in an Edmund-Bühle high acuum a c-mel ing sys em. The a c-mel ed bo oms (~2 cm diame e and ~0.8 mm hick) we e emel ed se e al imes o ge homogeneous samples. X- ay di ac ion (XRD) pa e ns we e eco ded a oom empe a u e using a B ucke AXS D8-Ad ance di ac ome e wi h Cu K adia ion on slices ~100 m hick cu om he bulk samples. Fo he momagne ic (TMG) expe imen s, he magne ic ield o a small magne (20 mT) was applied o he sample and he empe a u e a ia ion o he magne ic o ce was eco ded in a he mobalance (Pe kin-Elme TGA-7) as an appa en weigh change o he sample. The Cu ie empe a u e, TC, was de e mined om low ield magne iza ion cu es, by he “kink poin ” me hod. In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 4 The sa u a ion magne iza ion, Ms, was measu ed on samples ~5 mg a oom empe a u e wi h a Lakesho e 7407 ib a ing sample magne ome e (VSM), using a maximum applied ield o 15 kOe. Mössbaue spec a on he same samples s udied by XRD we e aken a 300 K in a ansmission geome y using a 57Co(Rh) sou ce, wi h he -beam pe pendicula o he ibbon plane. The alues o he hype ine pa ame e s we e e ined using NORMOS [12] and MOSFIT p og ams [13]. The isome shi alues a e quo ed ela i e o -Fe a 300 K. 3. Resul s 3.1 X- ay di ac ion X- ay di ac og ams o as-cas samples show ha he subs i u ion o Fe by Ga shi s he posi ion o di ac ion lines co esponding o bcc phase o pu e -Fe o smalle alues o 2. Figu e 1a shows, as an example, he XRD pa e n o Fe75Ga25 alloy. The inc ease o he la ice pa ame e , a, caused by Ga addi ion can be exp essed by (Fig. 1b): ya )1(00020.0)2(2869.0   [nm] (1) whe e y is he Ga con en (a . %) o he alloy. Addi ional weak e lec ions due o he possible occu ence o DO3 o de ing o he s uc u e a e no de ec ed. In ac , as i was said abo e, he simila i y be ween he a omic sca e ing ac o s o Fe and Ga makes his de ec ion di icul , unlike o FeSi alloys. 3.2 Magne ic p ope ies The sa u a ion magne iza ion, MS, a 300 K, shows a linea dependence wi h he Ga con en , y, up o 20 a . % Ga (see Fig. 2a.), ha can be exp essed by: In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 5 yM S)5(0.3)6(223  [emu/g] (2) The a e age magne ic momen pe Fe a om, <  Fe>, dec eases as he Fe con en dec eases (Fig. 2b). A linea dependence o <  Fe> wi h y is obse ed o Ga con en up o 20 %, ha can be gi en by: y Fe )3(004.0)3(24.2   [  B] (3) The di e en beha iou o MS and <  Fe> below and abo e y = 20 a . % sugges s a change in he s uc u al o de ing o he bina y alloy. The Cu ie empe a u e, TC, o he a c-mel ed alloys dec eases mono onously wi h he Ga con en o he alloy as can be obse ed in Fig. 2c. 3.3 Mössbaue spec ome y Fig. 3 shows Mössbaue spec a o he s udied alloys eco ded a oom empe a u e. The hype ine s uc u e is s ongly dependen on Ga con en . Fo y ≤ 20 a . % a six line pa e n is obse ed, wi h inc easing line wid hs as he Ga con en o he alloy inc eases. The Mössbaue spec um co esponding o Fe75Ga25 alloy is quali a i ely di e en o hose o alloys wi h lowe Ga con en , exhibi ing addi ional and sha pe lines ha sugges some s uc u al change. The i ing o he spec a was i s ied using se e al independen sex e s wi h ee wid h bu only he spec um co esponding o he alloy wi h 5 a .% Ga could be sa is ac o ily i ed using his model. Nei he he spec um o he 25 a .% Ga could be clea ly decomposed in o wo componen s wi h p opo ions 3:1, as could be expec ed o a s oichiome ic Fe3Ga wi h a DO3 s uc u e. The bes i ing o he spec a was a ained using a disc e e magne ic hype ine ield dis ibu ion (HFD) wi h a linea co ela ion be ween he magne ic hype ine ield and he isome shi o he componen s o he dis ibu ion in o de o ep oduce he In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 6 asymme ical shape o he spec a [14]. The quad upola spli ing was a e aged o ze o. The ob ained HFDs a e shown in Fig. 3 ( igh hand side). HFDs co esponding o y = 5 and 10 a . % Ga ange om 25 o 36 T and show no signi ican di e ences: only a small shi o he maximum om 32 T o 31.5 T and a small inc ease in he wid h o he dis ibu ion om 3.5 T o 4.6 T ( o a Gaussian i ing) wi h inc easing Ga con en . Fo y = 20 a . % Ga alloy, he HFD co esponds o a much b oade six-line pa e n spec um and anges om 18 o 36 T wi h a main maximum a 30.5 T and a shoulde a 21.5 T. The magne ic hype ine ield dis ibu ion o Fe75Ga25 alloy, ha anges om 16 o 36 T, consis s o wo clea maxima, labelled as “a” and “b” in Fig. 3, cen ed a 20 T and 30.5 T and wi h ac ion a eas o 0.54 and 0.46, espec i ely. Fo a co ec i ing o he spec um i was necessa y o add a numbe o componen s wi h magne ic hype ine ields anging om 1.5 o 16 T (~ 4 % o he o al Fe a oms). The a e age magne ic hype ine ield a 300 K dec eases wi h inc easing Ga con en (Fig. 4a) as does he a e age magne ic momen pe Fe a om, and a linea dependence be ween hese wo quan i ies is ound o Ga con en  20 a . % (Fig. 4c). The dec ease o <Bh > wi h y, o y up o 20 a . %, can be exp essed by a linea ela ion: yBh )2(23.0)3(1.33  [T] (4) The alue o <Bh > a y = 0 a . % o Ga is in ag eemen wi h he expec ed alue o Bh o pu e -Fe phase a oom empe a u e, 33.0 T. Fo compa ison, Fig.4a also shows he composi ional dependence o <Bh > o FeAl [15] and FeSi [16] alloys. A discon inuous jump a 20 a .% me alloid is encoun e ed o FeGa and FeAl alloys, bu his jump is no so clea o FeSi alloys. In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 7 The a e age isome shi (Fig. 4b) inc eases linea ly wi h Ga con en up o 20 a .% Ga ollowing he ela ion: yIS )5(0070.0)5(003.0     [mm/s] (5) The angle , de ined by he di ec ion o he magne ic hype ine ield and he p opaga ion di ec ion o he  ays, can be ob ained om he in ensi ies o he second and he hi d abso p ion lines o he spec a. Fo he p esen alloys, a alue o a ound 55 º e eals he absence o ex u e o magne ic momen s o all alloys. 4. Local o de modelling Using a binomial dis ibu ion, he p obabili y, Pnm, o a bcc en i onmen wi h n Ga a oms as nea neighbou s (NN), in he i s shell, and m Ga a oms as nex nea neighbou s (NNN), in he second shell is gi en by he exp ession: 8 6 ( ) ( ) ( ) ( ) n m n m NN NNN NN NNN nm Ga Ga Fe Fe P M x x x x                   (6) whe e )(NN U xand )(NNN U xa e he concen a ion o U a oms (Ga o Fe) in he se o 8 NN a oms o he i s shell and in he se o 6 NNN a oms o he second shell, espec i ely, ha su ounds he cen al Fe a om. The mul iplici y, M, can be calcula ed as: !)!6( !6 !)!8( !8 mmnn M    (7) Howe e , he composi ion o he neighbou hood o he Fe a oms mus be s ongly a ec ed, no only by he global composi ion, bu also by he o de ing o he c ys alline s uc u e. In a ully diso de ed A2 s uc u e, he Ga and Fe posi ions a e indis inguishable and hei dis ibu ion would be andom. The e o e, he a omic composi ion o he i s and second shells is he same, xFe and xGa, o Fe and Ga a oms, espec i ely. Howe e , i is impo an o no e ha using Mössbaue spec ome y (MS), om he 15 a oms (one cen al su ounded by 8 as NN and 6 as NNN) which a e p obed In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 8 and o m he clus e uni , he cen al one is o ced o be a Fe a om. The e o e, he p obabili ies o inding a Fe a om o a Ga a om in he neighbou hood o he p obe a e modi ied wi h espec o he global composi ion (Fe100-yGay, wi h xFe = (100-y)/100, xGa = y/100). In ac , he a e age numbe o Fe a oms in a g oup o 15 is 15xFe and he a e age numbe o Ga a oms is 15xGa. Taking in o accoun ha he cen al p obe is a Fe a om, he a e age numbe o Fe a oms in he 8 NN plus 6 NNN will be 15xFe-1 and, hus, he co ec ed Fe concen a ion, 14/)115(  Fe co Fe xx , in he NN plus NNN en i onmen is dec eased wi h espec o he global alue, and he co ec ed Ga concen a ion, 15 /14 co Ga Ga x x, is enhanced wi h espec o i s global concen a ion in he alloy. In he case o o de ed s uc u es, he posi ions o Ga and Fe a oms in he elemen a y cell a e dis inguishable. Fo a pe ec o de ed DO3 s uc u e, only possible o an alloy composi ion o Fe75Ga25, a Ga a om is always su ounded by 8 Fe a oms as NN and 6 Fe a oms as NNN, bu o Fe a oms, wo di e en si es a e p esen ; namely, 1/3 o he Fe a oms ha e 8 Fe a oms as NN and 6 Ga a oms as NNN (D si e) and 2/3 ha e 4 Fe and 4 Ga a oms as NN and 6 Fe a oms as NNN (A si e). (Table 1). Fo alloy composi ions Fe100-yGay wi h y < 25 a . %, he e is no possibili y o a pe ec o de ed s uc u e as he numbe o Fe a oms is in excess and he numbe o Ga a oms is less han he needed. The e o e, we assume a “maximum o de ed” s uc u e in which Ga a oms will be always loca ed in hei co ec si es and he Ga si es which can no be occupied by Ga a oms will be illed wi h he exceeding Fe a oms. Thus, “maximum o de ed” s uc u e implies ha a Fe si e will ne e be occupied by a Ga a om bu some Ga si es will be occupied by Fe a oms, esul ing h ee di e en si es o Fe (Table 1): A and D si es, which a e co ec Fe si es, and Ga si es occupied by Fe In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 9 a oms. The dis ibu ion o he 100-y Fe a oms will be as ollows: 50 will be in A si es, 25 in D si es and 25-y Fe a oms will be subs i u ing Ga a oms. Each Fe a om in an A si e in a pe ec o de ed DO3 s uc u e has 4 Ga a oms as NN bu o a Ga con en lowe han 25 a . %, a Fe a om in an A si e could ha e 4, 3, 2, 1 o 0 Ga a oms as NN. Analogously, he possible con igu a ions o a Fe a om in a D si e anges om 6 o 0 Ga a oms as NNN. Finally, a Fe a om in a “Ga a om-si e” will always ha e 0 Ga a oms as NN and 0 Ga a oms as NNN (Table 1). Taking in o accoun he p e ious conside a ions o ob ain he concen a ion o Fe and Ga a oms in he NN and NNN se s o a oms, he p obabili ies o he di e en con igu a ions can be calcula ed using equa ion (6). The esul s o diso de ed and o de ed s uc u es a e shown in igu es 5 and 6, espec i ely. 5. Discussion (a) Alloys wi h low Ga con en (10 a . %) Assuming he e ec o he Ga a oms on he magne ic hype ine ield o be p opo ional o he numbe o Ga a oms in he i s shell, n, and he numbe o Ga a oms in he second shell, m, he a e age magne ic hype ine ield can be exp essed by:    mn nm mn nmh mPqnPB ,, 33 [T] (8) whe e q and a e he educ ion o Bh pe Ga a om in he i s and he second shell, espec i ely. The linea i y be ween he educ ion o Bh and he numbe o Ga a oms as NN (o NNN) yielding o q (o ) is no a s ong hypo hesis o low Ga con aining alloys (expec ed o be in a diso de ed s uc u e) as he mos p obable con igu a ions a e hose o 0, 1 o 2 Ga a oms as NN o NNN (Fig. 5). Fo ully diso de ed sys ems, he ela ionships be ween bo h Pnmn and Pnmm wi h y a e linea (Fig. 7). The e o e, om equa ions (4) and (8) i is possible o ob ain: In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 16 [15] D.S. Schmool, E. A aujo, M.M. Amado, M. Aleg ia Feio, D. Ma ín Rod íguez, J.S. Ga i aonandia and F. Plazaola, J. Magn. Mag. Ma e . 272-276 (2004) 1342. [16] M.B. S ea ns, Phys. Re . 129 (1963) 1136. [17] G. Inden and W. Pi sch, Z. Me allkde, 62 (1971) 627. In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 17 Table 1. De ini ion o he di e en Fe si es in a pe ec o de ed DO3 s uc u e and in a “maximum o de ed” s uc u e o Fe100-yGay alloys. S uc u e Si e NN Fe a oms NN Ga a oms (n) NNN Fe a oms NNN Ga a oms (m) Pe ec o de ed DO3 y=25 a .% Fe a om in D si e 8 0 0 6 Fe a om in A si e 4 4 6 0 Ga a om si e 8 0 6 0 “Maximum o de ed” y<25 a . % Fe a om in D si e 8 0  6  6 Fe a om in A si e 4  4 6 0 Fe a om in a Ga a om si e 8 0 6 0 In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 18 Figu e cap ions FIG. 1. (a) XRD pa e n co esponding o Fe75Ga25 alloy and (b) la ice pa ame e , a, o he bcc phase o FeGa alloys as a unc ion o he Ga con en o he alloy. FIG.2. (a) Composi ional dependence o he sa u a ion magne iza ion, MS; (b) a e age magne ic momen pe Fe a om, <  Fe>, a 300 K and (c) Cu ie empe a u e, TC, o Fe100-yGay alloys. FIG. 3. T ansmission Mössbaue spec a a 300 K and hei co esponding i ing (solid line) and magne ic hype ine ield dis ibu ions o Fe100-yGay alloys. FIG. 4. (a) Composi ional dependence o he a e age magne ic hype ine ield, <Bh >; (b) a e age isome shi , <IS>, o FeGa alloys. Fo compa ison, i is also shown he composi ional dependence o <Bh > o FeAl [12] and FeSi [13] bina y alloys on (a). (c) A e age magne ic hype ine ield, <Bh >, as a unc ion o he a e age magne ic momen pe Fe a om, <  Fe>, a 300 K. FIG. 5. P obabili ies, Pnm, o a Fe si e o ha e n Ga a oms as NN, in he i s shell, and m Ga a oms as NNN, in he second shell o a ully diso de ed A2 s uc u e, calcula ed using equa ion (6), o he di e en s udied alloys. FIG. 6. P obabili ies, Pnm, o a Fe si e o ha e n Ga a oms as NN, in he i s shell, and m Ga a oms as NNN, in he second shell o a “maximum o de ed” DO3 s uc u e, calcula ed using equa ion (6), o he di e en s udied alloys. FIG. 7. Summa o ies o he p oduc s Pnm  n and Pnm  m, as a unc ion o he Ga con en o Fe100-yGay alloys. FIG. 8. <Bh > dependence on he a e age numbe o Ga a oms as nea neighbou s, <n>, o bo h ully diso de ed and “maximum o de ed” s uc u es. The expe imen al Bh In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 19 alues co esponding o maxima “a” and “b” o he HFD o Fe75Ga25 alloy a e also shown. In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 20 FIGURE 1 20 40 60 80 100 0 5 10 15 20 25 2.86 2.88 2.90 2.92 (a) (220) (211) (200) In ensi y (a.u.) 2 The a (º) (110) (b) a (A) Ga con en (a .%) o In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 21 FIGURE 2 0 5 10 15 20 25 700 800 900 1000 1100 0 5 10 15 20 25 120 160 200 240 0 5 10 15 20 25 1.8 2.0 2.2 Ga con en (a . %) (c) (b) T c (K) (a) M s (emu/g) < Fe > ( B ) In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 22 FIGURE 3 0 10 20 0 10 20 30 0 10 -8 -4 0 4 8 0 10 20 30 40 0 10 20 P(B h ) x=20 x=10 x=5 x=25 (mm/s) Rela i e ansmission b Bh (T) a In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 23 FIGURE 4 0 5 10 15 20 25 0.00 0.06 0.12 0.18 0.24 0 5 10 15 20 25 24 28 32 2.3 2.2 2.1 2.0 1.9 1.8 24 28 32 <IS> (mm/s) Ga con en (a . %) (b) (a) FeGa FeAl FeSi <B h > (T) (c) <B h > (T) <Fe> (B) In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 24 FIGURE 5 0 2 4 6 8 0.00 0.05 0.10 0 2 4 6 Fe80Ga20 diso de ed P obabili y Ga a oms in 2nd shell (NNN) Ga a oms in 1s shell (NN) 0 2 4 6 8 0.0 0.1 0.2 0 2 4 6 Fe90Ga10 diso de ed P obabili y Ga a oms in 2nd shell (NNN) Ga a oms in 1s shell (NN) 0 2 4 6 8 0.0 0.2 0.4 0 2 4 6 Fe95Ga5 diso de ed P obabili y Ga a oms in 2nd shell (NNN) Ga a oms in 1s shell (NN) 0 2 4 6 8 0.00 0.05 0.10 0 2 4 6 Fe75Ga25 diso de ed P obabili y Ga a oms in 2nd shell (NNN) Ga a oms in 1s shell (NN) In e me allics. Vol. 15. Núm. 2. 2007. Pag. 193-200 h p://dx.doi.o g/10.1016/j.in e me .2006.05.007 25 FIGURE 6 0 2 4 6 8 0.0 0.2 0.4 0 2 4 6 Fe95Ga5 o de ed P obabili y Ga a oms in 2nd shell (NNN) Ga a oms in 1s shell (NN) 0 2 4 6 8 0.0 0.1 0.2 0 2 4 6 Fe80Ga20 o de ed P obabili y Ga a oms in 2nd shell (NNN) Ga a oms in 1s shell (NN) 0 2 4 6 8 0.0 0.1 0.2 0 2 4 6 Fe90Ga10 o de ed P obabili y Ga a oms in 2nd shell (NNN) Ga a oms in 1s shell (NN) 0 2 4 6 8 0.0 0.3 0.6 0 2 4 6 Fe75Ga25 o de ed P obabili y Ga a oms in 2nd shell (NNN) Ga a oms in 1s shell (NN)