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Fc(ij) y Fa(\000)e Fj(1) y Fb(\023)o(\025)1865
1362 y Fj(\(1)p Fd(b)p Fj(\))0 1499 y(where)k Fd(D)184
1506 y Fg(O)214 1511 y Fc(ij)264 1499 y Fj(is)f(the)h(b)q(ond)g
(strength)f(in)h(k)o(cal/mol,)f Fd(R) y Fg(O)1061
1511 y Fc(ij) y Fj(is)h(the)g(b)q(ond)g(distance)f(in)1617
1490 y(\027) y(A,)h Fd(\015) y Fg(ij)1759
1499 y Fj(is)f(a)h(scale)0 1589 y(factor,)g(and)e Fd(q)271
1596 y Fg(i)302 1589 y Fj(is)h(the)h(partial)e(c)o(harge)g(of)i(i)p
Fe(th)f Fj(atom.)21 b(The)14 b(results)f([11-13])g(for)h(the)h(deh)o
(ydrate)e(VPI-5)0 1679 y([5])j(are)f(summarized)f(in)h(T)l(able)h(I.)g
(W)l(e)g(\014nd)f(net)h(partial)f(c)o(harges)g(1.4)h(for)f(Al,)h(0.56)g
(for)g(P)l(,)f(and)h Fa(\000)p Fj(0.5)0 1768 y(for)d(O.)g(The)h(FF)e
(parameters)g(are)h(summarized)e(in)i(T)l(able)g(I)q(I.)h(W)l(e)g
(compare)e(them)h(with)g(results)g(from)0 1858 y(v)m(an)20
b(Beest)h Fe(et)f(al)p Fj(.)33 b([14])20 b(and)f(de)h(V)l(os)g(Burc)o
(hart)f Fe(et)h(al)p Fj(.)33 b([15].)f(The)20 b(FF)f(of)h(v)m(an)g
(Beest)h Fe(et)f(al)p Fj(.)33 b(uses)0 1948 y(large)17
b(\014xed)g(partial)f(c)o(harges)g(on)h(the)h(P\(3.4\))f(and)g
(O\(-1.2\),)g(while)g(the)g(FF)g(of)g(de)g(V)l(os)g(Burc)o(hart)g
Fe(et)0 2037 y(al)p Fj(.)22 b(uses)16 b(smaller)f(\014xed)h(c)o(harges)
f(of)i(Al\(0.56\),)g(P\(0.25\),)g(and)f(O\()p Fa(\000)p
Fj(0.18\).)150 2128 y(T)l(able)f(I)q(I)q(I)h(sho)o(ws)d(the)j(MS-Q)e
(FF)g(w)o(ell)g(repro)q(duces)g(the)i(exp)q(erimen)o(tal)e(structure)g
(of)h(VPI-5.)0 2280 y Fi(Ac)n(kno)n(wledgemen)n(ts)150
2371 y Fj(W)l(e)i(thank)f(Professors)f(Keith)h(E.)g(Gubbins)f(and)h
(Mark)f(E.)i(Da)o(vis)f(for)g(v)m(aluable)g(commen)o(ts.)0
2460 y(O.K.)11 b(appreciates)f(the)i(tra)o(v)o(el)f(funds)f(pro)o
(vided)g(b)o(y)h(RING)h(\(Researc)o(h)e(Information)g(Net)o(w)o(ork)h
(Grand)0 2550 y(Challenge)22 b(Program\))g(and)h(NEDO)g(\(New)i(Energy)
e(and)f(Industrial)g(T)l(ec)o(hnology)g(Dev)o(elopmen)o(t)921
2670 y(30-3)p eop
%%Page: 4 4
4 3 bop 0 37 a Fj(Organization\),)17 b(and)f(for)i(the)g(hospitalit)o
(y)e(pro)o(vided)g(b)o(y)i(the)f(MSC.)g(The)h(MSC)f(facilities)g(are)g
(sup-)0 127 y(p)q(orted)j(b)o(y)g(gran)o(ts)g(from)f(the)i(DOE-BCTR)f
(and)g(NSF)g(\(CHE)h(95-22179)e(and)h(CHE)h(92-100368\),)0
217 y(Chevron)h(P)o(etroleum)f(T)l(ec)o(hnology)g(Co.,)i(Asahi)f
(Chemical,)h(Aramco,)g(Ow)o(ens-Corning)o(,)e(Exxon,)0
306 y(Chevron)e(Chemical)g(Compan)o(y)l(,)h(Asahi)f(Glass,)h(Chevron)f
(Re\014nery)h(T)l(ec)o(hnology)l(,)f(Co.,)i(Hercules,)0
396 y(Av)o(ery)c(Dennison,)e(BP)i(Chemical,)e(and)h(Bec)o(kman)g
(Institute.)0 557 y Fi(References)73 649 y Fj([1])24
b(S.)14 b(T.)g(Wilson,)g(B.)g(M.)g(Lok,)h(C.)f(A.)h(Messina,)e(T.)h(R.)
g(Cannan,)g(and)f(E.)h(M.)g(Flanigen,)f(J.)h(Am.)150
738 y(Chem.)21 b(So)q(c.)h Fi(104)p Fj(,)16 b(1146)g(\(1982\).)73
830 y([2])24 b(O.)16 b(Kitao)g(and)g(K.)g(E.)h(Gubbins,)d(Chem.)21
b(Ph)o(ys.)h(Lett.)h Fi(227)p Fj(,)15 b(545)h(\(1994\);)h(J.)f(Ph)o
(ys.)21 b(Chem.)150 920 y Fi(100)p Fj(,)d(12424)g(\(1996\);)i(O.)f
(Kitao,)g(M.)f(Mik)m(ami,)g(K.)h(T)l(anab)q(e,)f(S.)g(Ono,)h(and)f
(K.E.)g(Gubbins,)150 1010 y(Recen)o(t)e(Researc)o(h)f(Dev)o(elopmen)o
(ts)h(in)g(Ph)o(ysical)f(Chemistry)h Fi(1)p Fj(,)g(281)g(\(1997\).)73
1102 y([3])24 b(M.)12 b(B.)g(Kenn)o(y)l(,)g(K.)g(S.)f(W.)i(Sing,)f(and)
f(C.)h(R.)g(Theo)q(c)o(haris,)f(J.)h(Chem.)20 b(So)q(c.,)12
b(Chem.)20 b(Comm)o(un.)150 1191 y(1991,)c(974.)73 1283
y([4])24 b(L.)17 b(B.)f(McCusk)o(er,)f(C.)i(Baerlo)q(c)o(her,)e(E.)i
(Jahn,)e(and)h(M.)g(Bulo)o(w,)g(Zeolite)h Fi(11)p Fj(,)f(308)g
(\(1991\).)73 1375 y([5])24 b(C.)16 b(E.)h(Cro)o(wder,)e(J.)h(M.)g
(Graces,)g(and)f(M.)h(E.)h(Da)o(vis,)f(Adv.)22 b(X-ra)o(y)16
b(Anal.)22 b Fi(32)p Fj(,)15 b(507)i(\(1988\).)73 1467
y([6])24 b(M.)18 b(E.)h(Da)o(vis,)f(C.)h(Saldarriaga,)d(C.)j(Mon)o
(tes,)f(J.)g(Garces,)h(and)f(C.)g(Cro)o(wder,)g(Nature)g
Fi(331)p Fj(,)150 1557 y(698)e(\(1988\).)73 1649 y([7])24
b(K.)14 b(Kitaura)g(and)f(K.)i(Morokuma,)e(In)o(tl.)21
b(J.)13 b(Quan)o(tum)g(Chem.)21 b Fi(10)p Fj(,)14 b(325)g(\(1976\);)i
(T.)e(Komat-)150 1738 y(suzaki,)i(and)g(I.)g(Ohmine,)f(Chem.)22
b(Ph)o(ys.)f Fi(180)p Fj(,)15 b(239)h(\(1994\).)73 1830
y([8])24 b(T.)18 b(C)-29 b(\030)7 b(a\025)-25 b(g\020n,)19
b(E.)f(Demiralp,)f(and)h(W.)h(A.)g(Go)q(ddard)e(I)q(I)q(I,)i(\\New)g
(In)o(teratomic)f(P)o(oten)o(tials)f(F)l(or)150 1920
y(Silicas,")12 b(MRS)g(Spring)f(1997)h(Meeting)h(Pro)q(ceedings,)f(338)
h(\(1997\);)h(E.)e(Demiralp,)g(T.)h(C)-29 b(\030)7 b(a\025)-25
b(g\020n,)150 2010 y(N.)20 b(T.)h(Hu\013,)g(and)e(W.)i(A.)f(Go)q
(ddard,)g(I)q(I)q(I,)h(\\New)f(In)o(teraction)g(P)o(oten)o(tials)f(for)
h(Glass)f(Sim-)150 2099 y(ulations,")24 b(Pro)q(ceedings)e(of)i(XVI)q
(I)q(I)h(In)o(tl.)43 b(Glass)23 b(Congress,)g(pp)g(11-15,)i(Editors)d
(M.)h(K.)150 2189 y(Chouadry)l(,)15 b(N.)i(T.)f(Hu\013,)h(and)f(C.)g
(H.)h(Drummond)d(I)q(I)q(I.)73 2281 y([9])24 b(T.)14
b(C)-29 b(\030)7 b(a\025)-25 b(g\020n,)15 b(E.)f(Demiralp,)f(and)h(W.)h
(A.)f(Go)q(ddard)g(I)q(I)q(I,)h(\\Pressure)e(Induced)g(Phase)h(T)l
(ransfor-)150 2371 y(mations)j(in)g(Silica,")g(Microscopic)g(Sim)o
(ulation)e(of)j(In)o(terfacial)f(Phenomena)g(in)g(Solids)g(and)150
2460 y(Liquids,)i(V)l(ol.)29 b(492,)20 b(pp)e(287-292)h(\(1998\))g
(Editors)f(S.)h(Phillp)q(ot,)g(P)l(.)g(Bristo)o(w)o(e,)f(D.)h(Stroud,)
150 2550 y(and)14 b(J.)g(Smith.)21 b(N.)15 b(T.)f(Hu\013,)h(E.)g
(Demiralp,)e(T.)i(C)-29 b(\030)7 b(a\025)-25 b(g\020n,)14
b(and)g(W.)h(A.)g(Go)q(ddard)f(I)q(I)q(I,)h(\\F)l(actors)921
2670 y(30-4)p eop
%%Page: 5 5
5 4 bop 150 35 a Fj(A\013ecting)19 b(Molecular)f(Dynamics)g(Sim)o
(ulated)f(Vitreous)i(Silica)f(Structures,")g(Pro)q(ceedings)150
124 y(of)f(XVI)q(I)h(In)o(tl.)k(Glass)16 b(Congress,)f(pp.)22
b(61-66,)16 b(Editors)f(M.)i(K.)f(Chouadry)l(,)f(N.)i(T.)g(Hu\013,)g
(and)150 214 y(C.)f(H.)g(Drummond)e(I)q(I)q(I;)j(E.)f(Demiralp,)e(T.)i
(C)-29 b(\030)7 b(a\025)-25 b(g\020n,)16 b(and)f(W.)h(A.)h(Go)q(ddard)e
(I)q(I)q(I,)h(\\The)g(MS-Q)150 304 y(F)l(orce)21 b(Field)g(for)g
(C)i(Application)e(to)h(the)h(Quartz-Stisho)o(vite)d(Phase)h(T)
l(ransition)150 393 y(and)f(to)i(Silica)e(Glass,")h(Ph)o(ys.)35
b(Rev.)g(Lett.,)23 b()f(N.)g(T.)f(Hu\013,)h(E.)f(Demiralp,)f
(T.)150 483 y(C)-29 b(\030)7 b(a\025)-25 b(g\020n,)21
b(and)f(W.)h(A.)g(Go)q(ddard)e(I)q(I)q(I,)i(\\Molecular)f(Dynamics)f
(Sim)o(ulaton)g(of)i(Vitreous)f(Sil-)150 573 y(ica,")e(J.)f(Non)h
(Cryst.)26 b(Solids,)17 b()g(W.)h(A.)g(Go)q(ddard,)f(E.)h
(Demiralp,)e(T.)i(C)-29 b(\030)7 b(a\025)-25 b(g\020n,)17
b(S.)150 662 y(Hw)o(ang,)c(YH)h(Jang,)f(J.)f(Sefcik,)i(\\Dynamic)f
(Charge)f(Equilibration)f(force)j(\014eld)e(\(D-QEq-FF\))150
752 y(with)21 b(applications)e(to)i(phase)e(transitions,)h(surface)g(c)
o(hemistry)l(,)g(and)g(other)g(prop)q(erties)g(of)150
842 y(inorganic)f(systems,")h(Amer.)33 b(Chem.)f(So)q(c.)i
Fi(216)19 b Fj(700)h(\(1998\);)j(A.)d(Strac)o(han,)g(T.)g(C)-29
b(\030)7 b(a\025)-25 b(g\020n,)150 931 y(E.)18 b(Demiralp,)g(W.)g(A.)h
(Go)q(ddard,)f(I)q(I)q(I,)h(\\Theoretical)f(assesmen)o(t)f(of)i(phases)
e(of)i(MgO)f(from)150 1021 y(DFT)e(and)g(MD)g(sim)o(ulations,")e(to)j
(b)q(e)g(published.)48 1111 y([10])24 b(A.)17 b(K.)f(Rapp)o(\023)-24
b(e)16 b(and)g(W.)g(A.)h(Go)q(ddard)e(I)q(I)q(I,)j(J.)e(Ph)o(ys.)21
b(Chem.)g Fi(95)p Fj(,)16 b(3358)g(\(1991\).)48 1200
y([11])24 b(The)16 b(optimization)g(of)g(the)h(FF)e(uses)h(FF)o(OPT)f
([12])h(in)g(conjunction)f(with)i(Cerius2)e([13])h(and)150
1290 y(the)h(MSC)f(v)o(ersion)f(of)i(P)o(olygraf)e([13].)48
1380 y([12])24 b(S.)17 b(Dasgupta,)f(T.)h(E.)h(Y)l(amasaki,)e(and)h(W.)
g(A.)h(Go)q(ddard)e(I)q(I)q(I,)i(J.)e(Chem.)24 b(Ph)o(ys.)f
Fi(104)p Fj(,)16 b(9 y(\(1996\).)48 1559
y([13])24 b(Cerius2)12 b(and)g(P)o(olygraf)h(are)f(from)h(the)g
(Molecular)f(Sim)o(ulation)f(Inc.,)j(San)e(Diego,)i(California.)48
1649 y([14])24 b(B.)19 b(W.)g(H.)g(v)m(an)h(Beest,)g(G.)f(J.)f(Kramer,)
g(and)g(R.)h(A.)g(v)m(an)g(San)o(ten,)g(Ph)o(ys.)28 b(Rev.)i(Lett.)g
Fi(64)p Fj(,)150 1738 y(1955)16 b(\(1990\).)48 1828 y([15])24
b(E.)15 b(de)g(V)l(os)g(Burc)o(hart,)f(H.)h(v)m(an)g(Bekkum,)h(B.)f(v)m
(an)g(de)g(Graaf,)g(and)g(E.)g(T.)g(C.)g(V)l(ogt,)g(J.)g(Chem.)150
1918 y(So)q(c.,)h(F)l(arada)o(y)f(T)l(rans.)21 b Fi(88)p
Fj(,)15 b(1161)i(\(1992\).)921 2670 y(30-5)p eop
%%Page: 6 6
6 5 bop 81 35 a Fi(T)-5 b(able)20 b(I.)25 b Fj(P)o(artial)15
b(c)o(harge)h(for)g(VPI-5.)p 507 151 937 2 v 507 168
V 507 240 a(A)o(tom)128 b(MS-Q)887 222 y Fg(a)
y Fj(BKS) y Fg(b) y Fj(BBGV)
y Fg(c)p 507 282 V 507 346 a Fj(Al1)194 b(1.
b(1.4)184 b(0.56)507 426 y(Al2)194 b(1. b(1.4)184
b(0.56)507 506 y(P1)211 b(0. b(3.4)184 b(0.25)507
585 y(P2)211 b(0. b(3.4)184 b(0.25)507 665 y(O1)174
b Fa(\000)p Fj(0. b Fa(\000)p Fj(1.2)145 b Fa(\000)p
Fj(0.18)507 745 y(O2)174 b Fa(\000)p Fj(0. b
Fa(\000)p Fj(1.2)145 b Fa(\000)p Fj(0.18)507 825 y(O3)174
b Fa(\000)p Fj(0. b Fa(\000)p Fj(1.2)145 b Fa(\000)p
Fj(0.18)507 904 y(O4)174 b Fa(\000)p Fj(0. b
Fa(\000)p Fj(1.2)145 b Fa(\000)p Fj(0.18)507 984 y(O5)174
b Fa(\000)p Fj(0. b Fa(\000)p Fj(1.2)145 b Fa(\000)p
Fj(0.18)507 1064 y(O6)174 b Fa(\000)p Fj(0. b
Fa(\000)p Fj(1.2)145 b Fa(\000)p Fj(0.18)507 1143 y(O7)174
b Fa(\000)p Fj(0. b Fa(\000)p Fj(1.2)145 b Fa(\000)p
Fj(0.18)p 507 1179 V 507 1196 V 150 1341 a(The)16 b(n)o(um)o(b)q(er)f
(of)i(atoms)f(is)g(same)g(as)g(Cro)o(wder)f Fe(et)i(al)p
Fj(.)22 b([5].) y Fg(a) y Fj(Presen)o(t)16
b(w)o(ork.) y Fg(b) y Fj(Reference)g(14.)0
1402 y Fg(c)20 1420 y Fj(Reference)h(15.)58 1560 y Fi(T)-5
b(able)20 b(I)r(I.)k Fj(FF)16 b(parameters)f(for)h(AlPO)840
1567 y Ff(4)862 1560 y Fj(.)p 484
v 484 1693
V 737 1757 a Fd(R)775 1764 y Fg(O)805 1769 y Fc(ij)1027
1757 y Fd(D) y Fg(O) y Fc(ij)
y Fd(\015) y Fg(ij)750 1837 y Fj(\()769 1828
y(\027)769 1837 y(A\))149 b(\(k)o(cal/mol\))p 484 1881
V 484 1945 a(O-O)140 b(3.7910)h(0.53633)f(10.
2025 y(Al-Al)116 b(3. b(0.29556)f(11.
2105 y(P-P)150 b(3. b(0.29556)f(11.4
y(Al-O)128 b(1. b(27.315)165 b(8.4
y(P-O)145 b(1. b(51.381)165 b(8.4
y(Al-P)133 b(4. b(0.29556)f(11.7139)p 484 2376
V 484 2393 V 921 2670 a(30-6)p eop
%%Page: 7 7
7 6 bop 35 35 a Fi(T)-5 b(able)20 b(I)r(I)r(I.)j Fj(Structural)15
b(parameters)g(for)h(VPI-5.)p 239 211 1472 2 v 239 228
V 503 292 a(Cell)g(P)o(arameters)f(Bond)h(Distance)141
b(Bond)16 b(Angle)639 372 y(\()658 363 y(\027)658 372
y(A\))276 b(\() y(\027) y(A\))336 b(\(deg\))p
239 416 V 239 480 a(Expt)346 462 y Fg(a)536 480 y Fj(18.9)106
b(8.1)g(1.68)79 b(1.54)h(172.9)65 b(126.7)h(174.9)239
560 y(MS-Q)15 b(FF)450 542 y Fg(b)536 560 y Fj(19.1)106
b(8.6)g(1.67)79 b(1.58)h(168.8)65 b(137.0)h(177.8)239
640 y(BKS-FF)424 622 y Fg(c)536 640 y Fj(18.9)106 b(8.4)g(1.75)79
b(1.51)h(161.3)65 b(137.0)h(173.9)p 239 672 V 239 689
V 150 858 a(O)189 865 y Ff(1)211 858 y Fj(:)22 b(a-axis,)16
b(six)g(O)g(mem)o(b)q(ers)f(ring.)21 b(O)907 865 y Ff(2)929
858 y Fj(:)h(four)16 b(O)g(mem)o(b)q(ers)f(ring.)21 b(O)1496
865 y Ff(3) y Fj(:)h(c-axis.)150 920 y Fg(a)174
938 y Fj(Reference)16 b(5.)461 920 y Fg(b)481 938 y Fj(Presen)o(t)g(w)o
(ork.)802 920 y Fg(c)823 938 y Fj(Reference)g(14.)921
2670 y(30-7)p eop
userdict /end-hook known{end-hook}if