ZSM-48: DO Family

Intergrowth Family ZSM-48

Periodic Building Unit


Periodic Building Unit (PerBU):

Layer symmetry	P m m (2)

2D cell parameters	a = 8.26 Å	b = 24.99 Å	gamma = 90°

References
	Schlenker, J.L. Rohrbaugh, W.J., Chu, P., Valyocsik, E.W. and Kokotailo, G.T.
		"The framework topology of ZSM-48: a high silica zeolite"
		Zeolites, 5, 355-358 (1985)
	Lobo, R.F. and van Koningsveld, H.
		"New description of the disorder in zeolite ZSM-48"
		J. Am. Chem. Soc., 124, 13222-13230 (2002)

Connectivity pattern

Examples

The layers are stacked along the [001] direction using the following connectivity patterns

Symmetry Operation^*	Translation^*	Comment	Image
	1/3b	equivalent to 1/2 a -1/6 b
	1/2 a + 1/3 b	equivalent to -1/6 a

^* relative to the previous layer


Effect on channel system
	The disorder does not block the 1-dimensional channel system

Simplest ordered end members

The polymorphs for ZSM-48 were designated with numbers in reference 2 above and in the pdf linked in the "PDF" pulldown in the header. To be consistent with the other entries in this website, the polymorphs were renamed with capital letters. The corresponding numbers are indicated with each polymorph below.


Polymorph RFE

Cell Parameters:	orthorhombic	I m m a: (# 74)
	a = 8.2570 Å	b = 14.5619 Å	c = 20.3137 Å
	α = 90.000°	β = 90.000°	γ = 90.000°
	Volume =	2442.5 Å³
Framework Density (FD_Si):	19.7

	Ring sizes (# T-atoms):	10 6 5 4
	Channel dimensionality:	Topological (pore opening > 6-ring): 1-dimensional

Maximum diameter of a sphere:
	that can be included	6.36 Å
	that can diffuse along	a: 5.59 Å	b: 2 Å	c: 1.81 Å
		addional volume data

Composite Building Units:


afi	mel	imf

This polymorph corresponds to Polymorph UDUD in reference 1 and Polymorph 6 in reference 2 above.

In this space group and setting, the PerBUs are stacked along [011]
Adjacent layers generated by the same connectivity pattern (same basic color) are shown with different shades for clarity

	Note: This polymorph corresponds to the ordered framework RFE


Polymorph ZSM-48_B

Cell Parameters:	monoclinic	C 1 2/m 1: (# 12)
	a = 24.9940 Å	b = 8.2570 Å	c = 12.6100 Å
	α = 90.0000°	β = 109.1860°	γ = 90.0000°
	Volume =	2457.8 Å³
Framework Density (FD_Si):	19.5

	Ring sizes (# T-atoms):	10 6 5 4
	Channel dimensionality:	Topological (pore opening > 6-ring): 1-dimensional

Maximum diameter of a sphere:
	that can be included	6.28 Å
	that can diffuse along	a: 1.99 Å	b: 5.48 Å	c: 1.82 Å
		[0 1 0] : 5.48 Å
		addional volume data

Composite Building Units:


lau	mel	imf

This polymorph corresponds to Polymorph 3 in reference 2 above.

In this space group and setting, the PerBUs are stacked along [001]
Adjacent layers generated by the same connectivity pattern (same basic color) are shown with different shades for clarity

	Note: This polymorph has NOT been observed as a pure ordered material